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By Bob Goemans
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The 'LIVING' Marine Aquarium Manual

Basic and Advanced Husbandry for the 'Modern' Marine Aquarium

by Bob Goemans

Chapter 16 - Coral Selection

Introduction

Let's now take a look at some invertebrate candidates for hobbyist aquariums, and say 'some' since it's impossible to list everything that could be kept in reef aquariums or some types of fish-only aquariums. Some more successfully than others. Because of that I'll mostly stay with the better known, fairly easy to maintain species, yet also mention some that are considered interesting and/or possibly tempting, but poor choices along with the reasons for that position.

In 'this' chapter those of interest fall within the Phylum Cnidaria, which in turn is subdivided into four classes. Three of these classes have species not commonly seen or maintained in regular hobbyist aquaria, however that is not to say some of them are not available nor interesting. Yet they do require "very" specific care and/or have specialized environmental needs and therefore are only suited for hobbyists that wish to maintain focused environments, e.g., those in the Class Scyphozoa (Jellyfish) and Class Hydrozoa (Fire corals and Lace corals). Nevertheless a few species in these classes will be mentioned, as all are sometimes available in the trade, yet rarely or via special order.

As for the Class Anthozoa, that mainly of interest here, it is further divided into three subclasses having several orders, families, subfamilies and genera, with many of their more common species in the trade discussed here.

Furthermore, although many of the species in some of these categories have common names, those may be different in areas around the globe. Therefore, where there are species easily recognized by their common name, e.g., 'Mushroom Corals,' that terminology will be used. Yet where there are many in a genus having wide interest with many different and confusing common names, such as those considered to be "Leather Corals," I'll place their genus name in both the Table of Contents and in the associated chapter (16 & 17) in italics to indicate there are many species to research further.

Keep in mind the Class Anthozoa contains soft 'and' stony corals, along with gorgonians, zoanthids, sea anemones, and corallimorpharians (mushroom corals). For the sake of discussion, its Subclass Hexacorallia contains both and will be divided here in this chapter into two separate areas, one containing the soft species, and one containing the stony species.

In the next chapter, 'other' invertebrates such as shrimp, clams, sponges, and worms of interest will be discussed.

(Please keep in mind all underlined word(s) are linkable files - just click on them and be taken to its content/photo. Also, all shown photos are clickable, which often allows a larger file to be seen.)

And note, as in this chapter you will see some references to 'visit my Articles page or Animal Library' for more information on different species. All are posted on my website saltcorner.com.

Lets begin by first discussing some generalities.

Phylum Cnidaria - Corals

When people first looked upon coral animals they thought them plants. Upon further investigation and study they found two distinct types of animals - reef-building corals and non reef-building corals.

Ahermatypic corals - called 'octocorals' because they have polyps with eight tentacles - are known as non reef-building corals and contribute very little or nothing to building reefs. They also differ from hermatypic corals called reef-building corals in the way they attain most of their nutrients, and are found in many warm 'and' cold environments in both shallow and deep areas. Considered 'soft corals' by aquarists and can generally be thought of as carnivores as they consume whatever they can catch. Most are slow growers and do not precipitate calcium carbonate skeletons as fast as reef-building corals, while others simply form small skeletal pieces called sclerites, sometimes referred to as spicules that help provide some structural support for their more often soft bodies. Spicules have also become a means to more properly identify some of these animals. However, there are some soft corals that do not fit the soft coral term, such as Heliopora coerulea, called the Blue Coral, and Tubipora musica called Organ Pipe Coral. They are described further along in this chapter.

Hermatypic corals - called 'hexacorals' because their polyps have six or multiples of six tentacles, and also secrete a solid calcareous skeleton - are often referred to as stony corals by aquarists and are also carnivorous yet receive a vast amount of their nutritional needs from a single-celled dinoflagellate alga belonging to the genus Symbiodinium called zooxanthellae. They live in more warm and shallow environments where sunlight penetrates and photosynthesis occurs, as zooxanthellae only survive in mid 60 to a high 80º F temperature range (16 - 27ºC). In this mutualistic symbiosis, zooxanthellae utilize the animals' waste products, such as carbon dioxide, and supply its host about 90% of its nutritional needs, e.g., oxygen, glucose, glycerol and other nutritious organic substances. Along with providing valuable foodstuffs, zooxanthellae contribute to the precipitation of the calcium carbonate skeleton material by maintaining a slightly higher internal pH. It could be asked what do zooxanthellae get besides a safe and comfortable home. It is thought that since the water surrounding the reefs is so nutrient poor, zooxanthellae also get compounds consisting of phosphate and nitrogen from their hosts that is needed for their continued wellbeing.

As to the coral polyp itself, its quite simple in design with only sponges less complex. Basically, they have two main layers of skin/tissue with the outer layer called the ectodermis/epidermis and the inner layer the endodermis or gastrodermis. Between these two is a less prominent middle layer called the mesoglea where spicules and zooxanthellae may reside. One or more mouths, sometimes numbered in the thousands, open to allow food to enter where it finds its way to a connected stomach-like area called the gastrovascular cavity. Food is digested in this cavity and waste products are either expelled through the same opening or secreted through body tissue to the surrounding water/zooxanthellae since corals have no excretory system or kidneys. A ring of stinging tentacles often surrounds the mouth to aid in capturing various types of food/prey. Those that do not have tentacles use their body mucus to catch bacteria and plankton. Small filaments called cilia transport the captured foodstuffs to the mouth where it is then transported to the stomach and digested. Furthermore, corals tend to feed around the clock in the wild, therefore those that want to feed their corals might be wise to feed very small amounts, e.g., live algae cultures, various kinds of different size algae cells, fish eggs, copepods, oyster larvae, etc., throughout the day. And there is equipment that can facilitate such endeavors if need be, yet additional attention to water quality needs to be high on the list of aquarium chores!

Besides tentacles armed with nematocysts, which is a harpoon-like projectile that stuns and captures prey, some corals can extend mesenteric filaments outward from the stomach where they partly digest prey too large to be swallowed immediately. Besides containing a vast amount of different chemical compounds used for either defense or offense, some corals exhibit long sweeper-like tentacles during evening hours that can clear out the competition for growing space downstream. Furthermore, they do not have a brain or nervous system, or a respiratory system, i.e., gills or lungs. Nor do they contain a circulatory system with blood or even the vessels to transport it.

Some corals grow into large colonies while other live a solitary existence. Many build an internal calcium carbonate skeleton to support themselves. They take many forms and often consist of numerous polyps/mouths joined together by a tissue covering where they share the internal flow of nutrients.

If desiring more information about coral anatomy and some associated topics, highly recommend reading 'Aquarium Corals, Selection, Husbandry, and Natural History' by Eric Bornemans (ISBN 1-890087-47-5)

Keep in mind I've already discussed two of the more important environmental conditions for placing corals in the aquarium, i.e., light and water movement. Where feasible in this chapter, I'll mention the preferred PAR value of the lighting that should impact the discussed creature and also the preferred speed of the water current that should impact the species.

In fact, let me restate those parameters here so you don't have to backtrack to find this information:

As to PAR impact, there are shallow water/fringing reef stony corals that require intense light to remain healthy/colorful, such as a PAR value of about 400 - 800. Then there are soft and stony corals/other animals liking medium light, such as a PAR value in the range of 100 - 400. As for the low light corals, such as mushrooms and others, they prefer a PAR value of about 50 - 100. For water motion, I've decided to relate it to the visible intensity of water motion on that of a long tentacle anemone. No visible tentacle motion is '0,' whereas a slight movement of some tentacles is '1.' If all the tentacles are gently swaying in the current it is '2.' If all tentacles are moving fairly fast and bouncing into each other it is '3.' Should all tentacles be driven with such force they are extended in one direction or unable to sway back to their central position it's '4.' Try to keep these values in mind, but if necessary revert back to this paragraph, as you will see them as - PAR - XXX & WM - X. Hopefully you'll find this quite helpful.

Finally, unless expressly mentioned, all will do well in the following water quality parameters: Calcium 380 - 430 ppm, Alkalinity 2.5 - 3.5 meq/l, pH 8.1 - 8.2, Specific Gravity 1.024 - 1.026, Magnesium - 1280 - 1350 ppm (relate to actual specific gravity), Phosphate < .02 ppm, and a temperature range of 76 to 84°F (25 - 29°C).

Lets first look at ahermatypic non-reef-building corals, those called soft corals Class Anthozoa), then in a separate discussion below that, those called stony corals, the hermatypic corals called reef-building corals.

The Soft Corals (Class Anthozoa)

Without going into a dissertation on Taxonomy, it will hopefully suffice to say there are several orders, suborders, families, genera, and species of major interest, with some species highly preferred. Lets begin with examining one particular species of soft coral that for all practicable purposes looks and feels like a stony coral.

Subclass Octocorallia

Order Helioporacea
Blue Coral

The species, Heliopora coerulea, also sometimes called Ridge Coral, forms massive encrusting columnar and branching formations along upper reef slopes and hardpan areas of lagoons in the Western Pacific. Usually seen in various shades of brown or tan with white-tipped edges that indicate new healthy growth. Generally quite abundant in some areas in the wild, especially in brightly lit shallow intertidal reef flat areas, e.g., 20 to 30 feet (6 - 9 m) where there is exceptionally good water movement, such as in and around areas where waves continuously pass overhead or experience the energy of breaking waves.

This is the only member in the Order Helioporacea, Family Helioporidae, and one of the few soft photosynthetic soft corals that actually contribute to reef building. It's technically not a soft coral, but because of its eight tentacled polyps, a trait associated with soft corals, it's commonly considered a soft coral. Its internal skeleton is "sky blue" because of its concentration of iron salts removed from surrounding seawater, hence its most popular name Blue Coral. The hard outer crust of calcium carbonate is brown due to the brown-colored zooxanthellae alga living in this outer covering. Its small olive colored polyps are interconnected by stolons, i.e., root-like extensions within its structure, and can shed a layer of its outer skin, similar to what some leather and porites corals normally accomplish to help remove unwanted coverings of algae, bacteria and/or detritus.

Very hardy and disease free in aquaria, but what was quite common in the trade due to its abundance in the wild, is unfortunately no longer common in the trade. It requires strong light, e.g., 4 - 6 watts per gallon (PAR 300 - 400), and does better under that coming from metal halides or LEDs than that coming from fluorescents (personal experience). If placed in areas receiving inadequate light, the white edging of its branches that indicate new growth will turn brown. This indicates the coral is increasing its zooxanthellae alga numbers to satisfy its present nutritional needs, therefore abandoning growth for the present. The specimen seen here in my aquarium was under metal halide lighting and had doubled its size in only two years without any special attention to its needs other than bright light and good water movement.

As for water movement, it should be placed where currents are fairly swift, (WM 2 - 3) yet not directly in front of outlets where the force of the flow would damage its polyps. Occasionally this coral will shed a thin layer of skin, a normal process, and blasts of water from a turkey baster can be used to remove any lingering areas of tissue/skin. No special feeding is required, since its food supply comes mostly from photosynthesis, and that absorbed from surrounding seawater. Otherwise, this non-aggressive soft coral, one that actually feels like a stony coral, is exceptionally easy to maintain given adequate light and water movement. It has always been one of my favorites! Unfortunately dried specimens are still sold in the ornament trade because of their blue coloring! Probably should be considered a more experienced hobbyist's coral, as water quality, better lighting and water flow are essential to its health.

Order Alcyonacea
Clove Polyps

These encrusting photosynthetic soft corals are members of the Family Clavulariidae and have small flower-like polyps that reproduce via creeping stolon's. They are mostly found along upper reef slopes and hardpan areas of lagoons and can cover many square yards (meters) in the wild. Polyp size varies, yet most attain a diameter of about 1 inch (2.5 cm). As for colors, most are shades of brown or green, with some being multicolored having central white areas surrounded by green fronds. In aquaria, they do well under moderate lighting (PAR 200 - 300) and prefer moderate water current (WM 2) and have common names such as Brown Daisy, Mat Polyps, Clove Polyps, Glove Polyps, Palm Tree Polyps, and Fern Polyps. There are four species that I know of: Clavularia hamra, C. inflata, and C. viridis from the Indo-Pacific Ocean, and C. modesto from the Atlantic Ocean. The species C. viridis is probably the most imported and quite popular species.

These are non-aggressive corals toxin-wise and do not posses stinging tentacles, yet, when located in places that suit them, may overgrow their closest neighbors. Nevertheless, they can be impacted by other aggressive corals, therefore space wisely and monitor their growth. Also, some angelfish such as those in the Centropyge family may nip or eat them. Considered a good beginners coral.

Star Polyps

Previously known as Pachyclavularia violacea, this species is more properly called Briareum violacea, or simply "Star Polyps" or "Starburst Coral." It may also belong in the Suborder Scleraxonia, Family Briareidae, however that's still unclear at this time and remains in the Suborder Stolonifera, Family Tubiporidae. This circumtropical photosynthetic green or brown encrusting soft coral is found in shallow to moderate depths along upper lagoon reef edges.

Under the right conditions it can spread quite quickly, e.g., about 1 inch (2.5 cm) or more per month. As it spreads, one can see tiny pin points of white in the purple looking rubbery layer of mat material that slowly extends outward and over adjoining substrate or even the sides of the aquarium. These "points of white" quickly develop into new polyps in the coming weeks as the expansion continues. It does best under medium light intensity (PAR 200 - 300), and requires good water movement (WM 2 - 3) to keep the cluster of polyps free of detritus. It will not tolerate hair algae, and can overgrow corals and kill them. In fact, I've had it completely cover a small leather coral within a few months. Color is greatly enhanced under lights that are high in the blue spectrum. Growth seems slowed when calcium levels fall below natural seawater levels, i.e., 400 ppm, and alkalinity falls below 3.0 meq/l. No doubt a good beginners coral.

Organ Pipe Coral

Tubipora musica is another photosynthetic coral in the above-mentioned family (Family Tubiporidae) that looks and feels like a stony coral, but because its polyps have eight tentacles, is considered a soft coral. In the wild, it is found in the Western Pacific Ocean: south of Japan, west to Africa's East Coast, and throughout the Red Sea where it inhabits upper reef slopes.

Its flower-like white and sometimes pink polyps extend from a cluster of red calcareous tubes that are interconnected by horizontal plates. Because of its shallow existence in the wild, it does best when placed directly under bright light, such as 4 - 6 watts per gallon (PAR 300 - 400). As for water movement, in the wild its often subjected to sweeping tidal changes or wave action, therefore water movement should directly impact the specimens (WM 2 - 3).

It has been long thought only one species exists, however, Sprung & Delbeek (1997) and more recently Vincent Hargreaves (2003) are of the opinion three or four species exist. Usually, it's difficult to find undamaged specimens as they are easily broken in shipment. But if a healthy and undamaged specimen were found it would make a good reef aquarium addition for the more experienced reef keeper. It's also a coral used extensively in the jewelry trade.

Leather Corals

The photosynthetic corals in the Suborder Alcyoniina, Family Alcyoniidae (Leather Corals) contain some of the more popular soft corals for reef aquariums. There are quite a few species and their specific technical identification can be difficult because many same species animals can be highly variable in appearance, i.e., shape can look quite different from another of the same species found elsewhere because of specific environmental factors, which include temperature, salinity, light intensity, water movement, and available local nutrients.

Once established, some can quickly go from tiny to gigantic in physical size in fairly short time periods. As to initial placement in the aquarium, its best to first placed the specimen in areas receiving somewhat low light levels. Then after becoming accustomed to its surroundings, possibly within a week or two, move to an area where lighting has greater intensity (PAR 200 - 400+) and space will allow for increased growth. These corals may also change their shade of color/protective pigments to some degree when they adjust their zooxanthellae level to match light intensity, possibly becoming somewhat a darker or lighter shade of brown depending upon intensity. Polyps generally retract at night.

Some species are occasionally pestered by a nudibranch in the genus Dendronotus, which can bore into the coral and eat inside tissue. Inspect all specimens occasionally, especially poorly performing specimens for dark areas or holes in their tissue. In some cases the specimen will have to be removed and while wrapped in a wet towel, surgery performed to investigate/remove any intruder found in the suspected tissue area. Simply flushing the wound with some freshwater will help heal the wound. Of course, remove and dispose of any pests when seen.

Most of these leather corals can easily be propagated by cuttings, and prefer moderate water movement (WM 2), with some tolerating hair algae and sub-optimal water quality. Occasionally species form Buds that tend to drop off and form new specimens. They can also be handfed, with many taking zooplankton, e.g., rotifers and/or newly hatch brine shrimp, and if so you may find their growth really accelerated. Also, every week or so its advisable to create a wave action by moving your hand through the water just above the animal or use a turkey baster to clean off any detritus buildup from the polyp areas, just like waves accomplish in the wild. They also seem to be sensitive to phosphate removing compounds containing aluminum oxide. Use this media carefully and/or in small amounts, as your leather coral may remain closed for days or weeks after placing too much of this chemical media in the system.

There are several genera of interest with their species commonly available.

Alcyonium

Common names depend on the shape and color of the existing species and include: Finger Leather Coral, Dead Man's Finger Coral, Encrusting Leather Coral, Bushy Soft Coral, Yellow Bush Coral, Colt Coral, Red Finger Coral, and Chili Pepper Coral. Colors are generally tan, somewhat gray, or yellowish. Most of these photosynthetic corals hail from the Indo-Pacific, yet some species are found in the Mediterranean, British Isles, North Sea and Atlantic Ocean. There are about 30 known species; yet as explained above, their growth factors in the wild make exact species identification somewhat difficult for the layman, hence all the common names. Furthermore, they are often confused with species in the genera Capnella, Cladiella, Lemnalia, and Nephthea.

Their growth usually takes a thick and encrusting form, many times with upward lobed finger-like projections, yet usually not much beyond heights of 6 - 8 inches (15 - 20 cm) for the entire animal. In some circumstances, especially where the specimen is hand fed phytoplankton foods, it can growth quite quickly and encompass/overgrow sessile neighbors. Found in calm turbid zones in the wild, they do well in closed systems with moderate light (3 - 5 watts per gallon) (PAR 200 - 300) and gentle water movement (WM 1 - 2). This is a group of organisms still in the stage of being identified, with possibly a morph from the Parerythropodium genus responsible for various color variations of A. fulvum, a more normally seen species in the trade. Overall these are hardy coral and well suited for the beginner.

Cladiella

Usually called Colt Coral, as are many in this family, and sometimes also called Finger Leather Coral, with all hailing from the Indo-Pacific. These tree-shaped photosynthetic soft corals have many branches that are further divided with finger-like projections. The erect, yet limber growth provides for an ever moving 'sway' when housed where gentle currents impact it. There are over 40 species having various shades of brown polyps, with most difficult to properly identify even for the experts. Once established, they can grow quite tall, e.g., 18 inches (45 cm), therefore colonies should have sufficient space between themselves and neighboring corals as they may shade-out nearby light needing species.

Even though not overly aggressive they are known to sting gorgonians, and in turn are said to be stung by mushroom corals. Cuttings from a healthy specimen will usually quickly take hold and grow into a new colony. Those in this genus, such as C. australis are quite slimy and feel very slippery to the touch. Feeding with microplankton a few times per week can accelerate growth. All are considered good corals for the beginner, as they do well in average water quality, with medium light intensity (PAR 200 - 300) and low water movement (WM 2).

Be aware there is a white nudibranch, probably Tritonopsilla alba, sometimes associated with this species. They feed on the coral mostly at night and often leave powdery deposits at the coral's base. Sometimes these deposits are so excessive the coral separates from its base. Viewing your aquariums at night, as with the aid of 'moonlights' is a good way to view for nighttime predators. Remove these frilly looking nudibranchs with tweezers when seen.

Lobophytum

Common names include Cabbage Leather Coral, Devils Hand Coral, Lobed Leather Coral, and sometimes Finger Leather Coral. These photosynthetic encrusting soft corals hail from the Indo-Pacific and have several forms, including upward extending finger-like extensions covered in polyps, and irregular ear-shaped growths with a sparse covering of short polyps. They are usually light tan in color and their body strengthening calcium carbonate sclerites can be seen through the skin tissue. In the wild, they can cover wide areas, with colonies sometimes reaching a yard (1 m) across and in height.

Can be considered an easy and hardy coral to maintain, yet there are some aspects that need to be taken into consideration. First though, they tend to do better under low to medium light (PAR 200) with moderate water movement (WM 2). Nevertheless, they can shed a toxic film that could touch other corals, causing them extreme stress. In fact, anemone and mushroom coral deaths from this film have been reported. Therefore it's wise to maintain good protein skimming and use activated carbon in the system to minimize slime and toxins from these corals.

And although easily propagated from cuttings, those cuttings while "in" the aquarium should be minimized with the precautions as mentioned above. After a cutting is taken, recommend replacing the activated carbon being used in the system. As for direct feeding, its not required except in very poorly lit systems (PAR <100), but if accelerated growth is desired, phytoplankton and/or zooplankton will suffice and then feed at least twice weekly.

Sarcophyton

This genus probably contains the most attractive of all "Leather Corals" and they have common names such as Umbrella Coral, Elephant Ear Leather Coral, Toadstool Coral, Leather Coral, and sometimes Mushroom Leather Coral. These photosynthetic broad column shaped corals with large mushroom shaped tops hail from the Indo-Pacific where they are found on reef flats and lagoons in generally shallow waters and appear in various shades of brown to yellow, sometimes reaching sizes of well over a yard (1 m) in width and height. They do well under moderate to bright light (3 - 5 watts) (PAR 200 - 300) with moderate water movement (WM 2 - 3) and occasional water surges to keep their surfaces free of detritus.

As with most leather corals they do not respond well to being handled too often. In fact, those in this genus are especially susceptible and seem to take longer periods of time to regain their full extension after each handling. It is also very natural for them to coat themselves with a white/waxy film from time-to-time or especially when disturbed. This layer of protective mucus carries away surface coatings of algae and bacteria that may have troubled the animal. It is also thought this mucus coating is way to get rid of a layer of excess carbon that was produced via photosynthesis. Nevertheless, this protective coating will be shed when the animal is ready to expand its polyps. Frequent shedding, however, could be a sign of poor water quality. Yet, size reduction at nighttime is thought to be a normal process in which the animal cleans itself of waste products. They also seem more susceptible to a nudibranch in the genus Dendronotus, which can bore into the coral and eat inside tissue, as mentioned in the introductory text above on Leather corals. See that text for care when it comes to this parasite.

Those in this genus also possess potent toxins that are used for clearing a path downstream for new growth or as a defense mechanism. Therefore, another animal, whether its a stony coral, soft coral, or anemone can be stressed if not killed when it comes in contact with its body. Providing it space for expansion, and the use of a quality protein skimmer and activated carbon are good ways to minimize problems. And even though bright light will no doubt help its zooxanthellae produce all the nutrition needed, its possible to feed various plankton-like products several times a week to encourage additional growth. It's another soft coral having the same water quality factors as the above in this family, and also considered a good beginners coral when its simple needs are provided.

Sinularia

Common names include Scalloped Leather Corals, Finger Leather Coral, Flexible Coral, Cabbage Leather Coral, Spaghetti Coral, and Knobby Leather Coral. These photosynthetic soft corals hail from the Indo-Pacific and there are well over 50 species, some having irregular shaped growth with a sparse covering of short polyps and others having upward extending finger-like extensions covered in polyps. They are usually light tan in color and prefer direct light bright light (PAR 300+) and fairly swift water movement (WM 2 - 3).

It's known that some species are quite toxic to other genera corals, i.e., can at a minimum inhibit or stunt their growth, especially where some Acropora, Catalaphyllia, Euphyllia, Plerogra and Porites species are concerned. This mechanism in the wild is used to clear areas for their growth, therefore its recommend quality protein skimming and activated carbon be utilized at all times in systems containing these animals. As for those wanting to propagate this species by fragmentation, recommend doing it outside the confines of the aquarium if feasible, and allowing the "frags" and mother colony to heal in a quarantine tank before any portions are returned to the show aquarium.

Possibly a good coral if maintaining a fish-only tank containing "coral" pickers, as this species is something most fish would not find tasty! It's also a good beginners coral, as its requirements are fairly simple, and direct feeding with plankton-like foods is not required unless additional growth is desired. And besides, occasionally, some nice green colored specimens show up in the trade.

Christmas Tree Coral/Medusa Coral

The species Studeriotes longiramosa is not a commonly found coral, yet one that is easily harvested since it occurs in shallow to medium water depths with somewhat turbid conditions having moderate water movement and where it is found firmly 'rooted' into soft sand and rubble bottom areas. It hails from the Indo-West Pacific, with the Tropical West Pacific, specifically Indonesia, Singapore, and the Philippines providing the most specimens. Its other common names include Snake Locks Coral and Pine Tree Coral.

This non-photosynthetic soft coral tends to expand upwards during daylight hours to feed on drifting plankton, and withdraws into its base during nighttime hours. Generally, brown or gray colored branches on a white column with a very pale brown/near white colored base.

Occasionally available in the trade, yet not overly popular as it's a difficult coral to maintain long-term. No doubt an oddity, as this coral needs to have its base firmly planted into the substrate which should be composed of fine sand where it will send out 'roots' (tendrils) to anchor itself. Low light, 2 watts per gallon (PAR <100) and moderate to good water movement (WM 1 - 2) suits it well. Since this species is non-photosynthetic it requires hand feeding in captivity. During daylight hours it will expand upwards and form a 'tree-like' structure where its branches with small polyps should be fed meaty type foods, e.g., rotifers, newly hatch brine shrimp or a zooplankton-type product at least twice daily. During evening hours the branches are folded inward and pulled downward into the column as it retracts for the remaining nighttime hours, almost like an anemone retracting its tentacles.

Take note, these corals have a poor record of survival in closed systems and unless willing to provide its exacting needs they will slowly waste away where starvation is the number one killer of this species in aquaria. And there is no known record of successful propagation, in fact just the opposite, as they seem to deteriorate quite quickly when cuttings are taken. However they are not overly fussy about water quality, as more turbid/murky conditions suit it quite well. Definitely a coral needing an environment specifically suited to its needs.

African Tree Coral

Often misidentified and called "Colt Coral" this photosynthetic species, Capnella imbricata is one of seventeen members in the Family Nephtheidae. It was formally called Nephteidae arboreum or Lemnalia africana with its most widely accepted common name being "African Tree." It hails from the Indian Ocean and Eastern African coast where it inhabits coastal shore and reef slope rubble areas experiencing good water movement. It grows/looks somewhat similar to Colt Coral, however, this species has a very dry feel to its tissue, not the slimy feel associated with the species Cladiella australis, which is commonly called the Colt Coral. In fact, this is the way to tell the two apart! It also has a tendency to drop small branches, with each turning into a clone of the parent colony.

It may reach a tree-like structure attaining a height of about 14 inches (35 cm) and is usually a tan or cream color. Even though photosynthetic, they tend to do better if fed microplankton-type foods several times per week and are placed under moderate light (PAR 200) with gentle to good water movement (WM 1 - 2). They have a wide temperature range, e.g., 68 to 83°F (20 - 28°C). Aggression-wise, experience with this species has show they are not aggressive and can touch other corals without doing harm. In fact, I had a mushroom coral actually growing on the main stem of my specimen, which I had maintained for over ten years. However, other more aggressive corals will do them harm, so use commonsense when placing them in aquaria. Not considered a beginners coral because of its need to be directly fed several times a week.

Carnation Corals

These are also in the Family Nephtheidae and there are several species in the genus Dendronephthya, which have common names such as Tree Coral, Ledge Coral, and Cauliflower Coral. These colorful, non-photosynthetic bushy tree-like soft corals hail from the Indo-Pacific and Red Sea where they can reach colonies about 1 yard (1 m) in width and possibly 2 yards tall. They inhabit shaded vertical surfaces, usually on deep-water ledges, under overhangs and/or in caves experiencing gentle currents bringing them a steady supply of phytoplankton.

In aquaria, they require a shady location, moderate water movement (WM 1 - 2), and direct feeding with a phytoplankton product at least twice "daily." They tend to deflate during daylight hours, yet fill with water at night as it does in the wild when phytoplankton is more normally available. Therefore, its deflated appearance during daytime in aquarium shops is quite normal. But this does present a problem once in the home aquarium, as it will have to be coaxed back into an inflated specimen by introducing large amounts of phytoplankton into the aquarium water, or feeding during evening/nighttime hours when it normally inflates. This is why I only recommend well-experienced aquarists purchase them, i.e., those understanding the species environmental needs and the capability to keep them corals well fed. Otherwise, they should not be purchased! Furthermore, only specimens attached to a piece of substrate, e.g., a piece of rock, should be purchased, and furthermore do not lay the specimen on the sandbed surface as it always should be placed on a ledge where currents sweep past it.

Large amounts of "green water" supplied at least twice a day may help keep daytime "open" specimens open. They usually have a white body with red polyps, yet other colorful species, e.g., red body with white polyps, or white body with yellow polyps are sometimes available. Again, not an easy coral to maintain because of its feeding requirements. Occasionally a small snail, Primovula bellocqae, can be found feeding upon this type coral and should be removed.


Waving Hand Coral

This and the following species appear in the Family Xeniidae. As for this species, its common names include Waving Hand Coral, Feather Coral, Glove Coral and Pulse Coral, and there is one species, Anthelia glauca, that commonly shows up in the trade. It hails from the Indo-Pacific and Red Sea where this encrusting photosynthetic soft coral usually inhabits protected, fairly shallow nutrient rich back reef areas, where gentle currents exist. Its tall, about 8 inches (20 cm), cylindrical-shaped polyps is part of an encrusting base that usually encompasses dead coral rubble and hardpan areas. Its polyps have 8 delicate pinnate tentacles, which have been seen to rhythmically open and close (pulse) in the wild. The most common color is a rich brown, however, I've also seen ashen gray, and/or very light tan specimens.

This soft coral is sometimes confused with Xenia, which is similar in appearance. Whereas Xenia polyps extend from its stalk or branches, the larger Anthelia polyps arise directly from its encrusting base, which is a good way to tell these two favorites apart from each other. Furthermore, Xenia is usually purchased because its polyp's tentacles have the capacity to pulse at regular intervals. Even though Anthelia polyp tentacles are also said to pulse in the wild, yet far less than do Xenia polyps, their pulsing in aquaria is quite infrequent. It is thought the pulsing tends to move dissolved organic laden water past the tentacles and/or is a form of respiration where dangerously high levels of dissolved oxygen are dissipated. One thing for sure, the reason for pulsing is still conjecture.

Anthelia does not need any specific direct feeding, therefore, only needs to be placed in a well lighted (PAR 200 - 300) area and where water quality is somewhat nutrient rich and gentle flows exist (WM 1 - 2). There are those that recommend activated carbon not be used, or at least, its use limited in aquaria containing this species. The same is true for Xenia, as it may affect their growth simply because this product lowers the aquarium's nutrient content. I have not found this to be true, as those specimens, both Anthelia and Xenia in my aquaria did extremely well in systems where water quality was 'excellent' and nitrogen-laden products where for all practicable purposes below what could be read on hobbyist test kits.

And even though Anthelia does not seem to contain any toxic chemicals, and therefore extremely compatible with other type corals it touches, it can spread quite fast under the right circumstances and simply overgrow its neighbors. Therefore provide sufficient space between it and its neighbor corals. This is certainly a good beginners coral as it does well with medium lighting and in a wide range of water quality environments.

Xenia

This photosynthetic soft coral hails from the Indo-Pacific and Red Sea where its are found in clear water lagoons and reef areas next to turbid inshore locations. Depending upon species and coloration, common names include Pulse Coral, Pom-Pom Xenia, Pumping Xenia, Red Sea Xenia, Blue Xenia, and Pulsing Xenia. Usually a mass of brown, long, yet thin-stemmed flower-like eight tentacle polyps interconnected at the base.

Depending upon geographical location and position in the area of collection some species appear slightly different in coloration having bluish, greenish, or red-pinkish colors, which can be attributed to their ultraviolet (UV) protection pigments. Therefore if a "Blue" Xenia is purchased don't be surprised if the blue color dissipates after it has been in the aquarium for a few weeks as the UV needed to maintain its coloration is often lacking.

Polyp stems can reach a height of about 6 inches (15 cm) or slightly more in some situations and the polyps can pulse, opening and sometimes closing about every one to five seconds. As mentioned above this may be a mechanism to rid excess oxygen, which can be highly toxic, and is thought not to be a feeding mechanism for those in this genus.

There have been discussions over the past decade noting this coral's sensitivity to nitrate-nitrogen levels over 5 ppm and that it may deteriorate if level exceeds 10 ppm. Personnel experience has shown it tolerates slightly higher levels, yet had its difficulties when levels reached 20 ppm. Also, it's seems to be sensitive to high pH levels, e.g., above 8.3, therefore caution is advised if adding buffers or products such as Kalkwasser. Its also been said these corals excrete a chemical that interferes with the growth of mushroom corals. Yet some aquariums seen containing both were all doing well. Nevertheless suggest Xenia be placed, if feasible, where water flowing past it will go directly to the filter system or sump containing activated carbon and not directly in line or past mushroom colonies.

Furthermore large colonies seem prone to 'crashes' where the entire specimen dissipates rapidly. Increasing water flow, and/or thinning out the colony can sometimes stop this. And increasing the bulk water iodine content has also shown to be helpful. If experiencing the brown protozoan Helicostoma, a gelatinous slime-like material that is sometimes involved in Xenia crashes, it can sometimes be cleared up by bathing the specimen in a weak solution of Lugols iodine (4 drops per liter of aquarium water). There's also a small crab, usually found in pairs and visible only at night that eats this soft coral, and which is usually found on top of closed polyp heads at night. If possible, remove with a tweezers.

Overall, bright light, e.g., from metal halides/LED's (PAR 200 - 300), medium to good water circulation (WM 2 - 3), and regular use of iodine additives are highly beneficial. No special feeding is required as their zooxanthellae seem very capable of providing most of their nutrition needs, with absorption of micronutrients in the surrounding water providing the remaining. And even though these corals are not aggressive they can spread quite quickly and can possibly overgrow adjacent corals. Since they are easily propagated with cuttings, almost all specimens now available in the trade are captive-propagated, with only a few coming from the wild. An ideal beginner coral and highly attractive because of its pulsating capability.

Gorgonians

Those in the Subclass Octocorallia, Order Gorgonacea are called 'horny corals' e.g., sea whips, sea fans, sea rods, and sea blades, and appear in the Suborders Scleractinia & Holaxonia. They mostly have a firm interior axial skeleton, usually a very pliable proteinaceous compound called Gorgonin or sometimes a calcareous compound that is covered with tissue.

Non-photosynthetic species, mostly coming from the Indo-Pacific, are usually found in deeper water where they colonize walls of caves or rocky/sandy bottom areas. Most require a temperature range between 73° to 81°F (23 - 27°C) and require good water movement (WM 2 - 3) and regular feedings of plankton-like foodstuffs.

As for Caribbean species, many are photosynthetic requiring bright light (PAR 300+) and good water movement as noted above. Both photosynthetic and non-photosynthetic will take plankton-like foodstuffs, i.e., rotifers, baby brine shrimp, and various commercially prepared plankton foods.

Their flexible branches are covered with individual polyps and come in various colors. Fan shaped horny corals grow with their flat side facing the current so as to allow them to feed more efficiently on the flow of plankton. This is the same way they should be placed in the aquarium.

Generally, only a specimen that is attached to a piece of rock should be purchased. That's because the area where it was broken off from its original structure could deteriorate rather rapidly. Nevertheless, if in healthy condition the bottom area of the stem could be embedded in epoxy putty to anchor its base and then attached to a piece of suitable-sized substrate/rock. Specimens that have blackened tissue or where the horny skeleton shows through should not be purchased.

Some Gorgonian will grow to the water's surface where they form ball-shape tips. Usually they will branch-out under this bulbous tip and the hobbyist can cut the branch about 2 inches (5 cm) below and secure the new stem elsewhere in the aquarium with underwater epoxy to form a new specimen.

Light as required, and provide good water flow along with weekly feedings of newly hatched brine shrimp to help keep these interesting invertebrate healthy. They will not tolerate unwanted forms of algae, and algae nutrients like phosphate, nitrate and silicate need to be closely monitored/minimized.

Keep in mind the Flamingo Tongue, Cyphoma gibbosum, a very pretty mollusk from the Caribbean is fond of eating gorgonian tissue and polyps. Therefore any aquarium with gorgonians should avoid this species. Also keep them out of the range of stinging corals, e.g., Bubble, Elegance, and Hammer corals.

There are few species commonly available, and all require specific care if they are to succeed.

Family Acanthogorgiidae

Those in this family form a fan-like structure and are found in the Central Indo-Pacific. They are not photosynthetic and inhabit reef slopes and are often found under overhangs. When collected they are sometimes cut into smaller sections and as such do not do well in aquariums. They are attractive structures, as they often have blue polyps making them eye-catching to say the least. If not attached to a piece of substrate, highly recommend placing the bottom stem into a glob of reef putty, then placing it in a area receiving indirect light and good water movement (WM 3). Then directly feeding its polyps with zooplankton and phytoplankton several times per day. Not seen in the trade too often, but if a healthy specimen is found and properly cared for, it makes a very pretty reef aquarium addition.


Family Anthothelidae

Diodogorgia nodulifera, commonly called the Yellow, Red, or Orange Finger Sea Rod (depending upon the color of its outer tissue) has polyps that are always white. It's widespread in the Tropical Western Atlantic: Southern Florida, Bahamas, Caribbean to Brazil. This non-photosynthetic coral is found in deeper water, 50 - 500 feet (15 - 160 m) and/or inhabits shaded areas, under ledges, cave walls, and deep sand/rocky areas. Colonies are loosely branched and range in height from 4 to 12 inches. It's quite attractive and frequently seen in the trade and should be placed in shady locations receiving good water flow (WM 2 - 3). Requires daily feedings with plankton-like foodstuffs. Generally short-lived in aquaria because its needs, especially that of diet are not met, therefore its recommended for only experienced aquarists.

Family Paramuriceidae
Red Gorgonian

One species in this family frequently showing up in the trade is the very pretty Red Gorgonian Swiftia exerta. This species is also found in the Western Atlantic (Florida & Bahamas) in waters about 50 feet (15 m) deep and those that are nutrient rich and experiencing moderate currents along coastal areas. Usually found inhabiting surfaces under overhangs or the interior walls of caves. Generally red polyps on orange branches yet may have some slight color differences depending upon where collected. Its preferred temperature range is 68 to 76°F (20 - 25°C).

Placement in the aquarium and its feeding is extremely important if there is to be any level of success with this species! It should be placed in a shady area, preferably a cave-like area receiving a gentle to moderate water current (WM 1) passing through it, i.e., from its opening to its opposite opening and where it's easy to direct a gentle flow, possibly from a turkey baster, of phytoplankton and zooplankton products upon its polyps at least 'twice' a day. And consider two feedings per day a very 'real' minimum, as three or four feeding per day are better, yet may still not be adequate for long term health. This species also seems to fair better in somewhat nutrient rich surroundings and where iodine additives are constantly used and monitored.

Keep in mind direct hand feeding of this species is 'absolutely' necessary, and it might be better if this species was maintained in a 'refugium-like' environment that is dedicated to sponges and other non-photosynthetic species and/or where system filtration can adequately handle the extra feeding attention this species requires. Also consider enriching its foodstuffs with commercial supplements having Highly Unsaturated Fatty Acids (HUFA) containing Omega-3 fatty oils, e.g., Eicosapentaenoic (EPA), Docosahexaenoic (DHA), and Alpha Linolenic Acid (ALA), as this seemed to have a positive effect on the specimen I maintained in a separate 20 gallon tank with two HOT filters and a white moonlight. Nevertheless, even with much dedicated care I did not have long-term (over one year) success with this species.

Unless it can be provided its needed environmental and nutritional needs, including a somewhat cooler water temperature as noted above, this is a species that is better left in the wild. Tempting yes, but difficult to maintain any length of time!

Family Plexauridae
Silver Sea Whip

There is one species in the Genus Muricea, that of M. laxa, that hails from the Western Atlantic Ocean: Florida, Gulf of Mexico, and the Caribbean, and one I've maintained for years in my aquariums. In the wild, this "photosynthetic" coral is found at various depths on coral fragments and rocky rubble. It has a temperature range of 68 to 79°F (20 - 26°C) and simply requires moderate light, 3 - 5 watts per gallon (PAR 200 - 300), very good water quality and moderate water movement (WM 3). Very hardy and easy to maintain.


Purple Frilly

Another photosynthetic and easy gorgonian to maintain is Pseudopterogorgia elisabethae, which also hails from the Western Atlantic: Florida and the Caribbean. It normally inhabits inshore and patch reef flats, slopes, and underwater plateaus, and has the same requirements as the above and attains a very pretty plume-like growth.


Sea Rod

Even though a fairly common name for several different species in this family, it is quite fitting for the species Plexaurella dichotoma. Also found in the Tropical Western Atlantic and Caribbean, its bushy growth can attain structures about one meter high. This photosynthetic gorgonian is better placed in the aquarium by wedging it between large rocks, as shown in the photo. If buried in the sand, it may rot. Easy to maintain, as it requires the same care as the above two discussed species.


Order Pennatulacea
Sea Pens

The Family Veretillidae has basically one species of interest, that being Cavernularia obesa, often simply called the Sea Pen. They come from Tropical and subtropical Indo-Pacific Ocean and are found in coastal soft sand and muddy bottom areas. These non-photosynthetic corals are cylinder-shaped filter feeders that can dig its lower portion into substrate and stand erect. Some specimens emit waves of bluish-green light at night to ward off predators. Most are light tan, but some orange and off-yellow specimens are seen from time-to-time. If the aquarium does not contain a deep substrate, a plastic bowl about three inches (7.5 cm) high filled with substrate may suffice.

It should be placed in a shady area where it receives a gentle water flow (WM 1), and directly fed phytoplankton and zooplankton products several times a day. Has a temperature range of 68 to 75°F (20 - 24°C) and is difficult to maintain long term and probably better left in the wild.

Subclass Hexacorallia

Sea Anemones

Anemones in this Subclass and the Order Actiniaria are basically simple, primitive animals. They range in size from .5 inch (1.25 cm) to over a meter in diameter. Their tube-shaped body is usually topped with a ring of tentacles, which selectively feed on planktonic organisms and/or small fishes. The ring of tentacles surround an area known as the oral disc and contains an opening in the center commonly called the mouth. Food is taken into this opening and waste matter or undigested food is expelled through the same opening. The body column sometimes referred to as a pedal column, serves as a means for locomotion or as a holdfast.

All anemones are considered carnivorous even though some utilize intense light to trigger symbiotic alga living in their flesh, which in turn produce a portion of their nutritional requirements. Should environmental conditions not be suitable, they can easily move to where light, water movement and feeding conditions are more favorable. In fact, frequently moving anemones' are a sign they are unhappy with their environment!

Using small nematocysts or stinging cells, which cover the tentacles and which are capable of firing a tiny dart connected with a thin filament into its prey, the anemone is very capable of capturing planktonic organisms and small fish. And they have few enemies, with other anemones, nudibranchs, sea stars and some fishes considered their main predators. Even though they cannot move swiftly, they have specialized defensive mechanisms that can deter potential predators, e.g., specialized nematocyst at the base of the tentacle; inflating defense tentacles called 'acrorhagi' located just below the oral disc; reducing body size; and, exuding quantities of nematocyst-laden mucous called 'acontia.'

Anemones may reproduce sexually or asexually by splitting and fragmentation. With some anemones, asexual reproduction results in the production of clones. Clones of the same specimen can intermingle without any harm to each other. Yet clones of a different individual, even though the same species will do battle with each other. They have been known to live in captivity for almost 80 years.

Clownfish domination of host anemones is simply nature's way for the fishes' survival. In the wild, very large anemones can be found with hundreds of different types of clownfishes living in a symbiotic relationship with "their" anemone. The question often arises what does the anemone get in return for hosting clownfishes? It seems the fishes waste, which is ammonium based, is used by the anemone's zooxanthellae as a nutrient source for their growth. In fact, studies have shown anemones grow four times faster if maintained with clownfishes.

With lots of anemones to go around in the wild, the living conditions are quite different than in the aquarium. With only one anemone in the aquarium, the strongest clownfish will dominate and weaker ones will be driven out. If all the clownfishes are added at the same time there is a better chance they will all settle down and live together in the same anemone. I find long tentacle Pacific anemones are by far the best choice for keeping clownfishes happy and healthy. Yet keep in mind the anemone must be of sufficient size, i.e., at least 5 inches (12.5 cm) across, or the clownfish may cause such disturbance the anemone is unable to feed itself.

When it comes to selecting anemones, always make sure their coloration is very good for the species desired; its inflated, their central orifice is closed/not misshaped or hanging open, the foot area is not torn, and its tentacles are sticky. Be especially attentive and make sure the shop clerk does not damage the foot area when removing it from the store tank. Many of the more popular anemones need good lighting intensity to survive, e.g., 4 - 6 watts per gallon (PAR 300 - 400+). As for water temperature, that's generally in the 75 - 82°F (24 - 27°C) range unless noted differently below, with salinity between 1.024 - 1.027. Also, good water movement (WM 2 - 3) is usually a key component for long-term success.

Keep in mind that sometimes anemones shrink or downsize their bodies if subjected to overly bright light conditions. To reduce or halt the production of oxygen by their photosynthetic alga cells, which can be damaging, they downsize so as to limit the surface area of their body to light. The proper care should be evident, simply downsize the available light.

As for feeding, small pieces of silversides, shrimp, krill, and fresh fish flesh, and/or whole small fish fed once to three times a week mostly suffice. Place the food morsel on the tentacles or near the central orifice. It should grab the food and feed itself. If the food falls out of the mouth, take it away and try again in a day or two. Only one anemone per tank is recommended unless the aquarium is over 100 gallons in size. And, keep in mind aggressive stony corals such as Euphyllia and Galaxea with long sweeper tentacles and large soft coals such as leather corals that compete for space with chemicals do not make good tankmates.

If you wish to keep an anemone, it should be the first addition to the tank, i.e., before adding soft or stony corals. After it settles into a spot, build your selection of corals around it. Avoid open access to the inputs of pumps and powerheads within the aquarium. Also, avoid placing heaters inside the aquarium. An anemone can be damaged if the heater turns on when the anemone is attached to it.

Host anemones of great interest are the bubbletip Entacmaea quadricolor, or the more erect column anemone, Heteractis magnifica, as are the long tentacle anemones, Macrodactyla doreensis, and what are called carpet anemones with even longer tentacles, e.g., Stichodactyla mertensii, Stichodactyla haddoni, Stichodactyla gigantea. Those found in soft sediment with only their oral disk exposed, such as Heteractis crispa (Leathery/Sebae Anemone), Heteractis malu and Heteractis aurora (Beaded/Sand/Button Anemone) are less popular.

Even though many different anemone species continue to make it into the trade, only a few have success in aquaria, and even then, not without understanding its particular needs. Then there are those that may look pretty, such as those in the Condylactus genus, yet have little other redeeming qualities. And then there are Rock anemones, which are serious 'pests' and need to be eliminated if they show up in the aquarium.

Two of the best publications to view most of the anemones of interest are: "Field Guide to Anemonefishes and their Host Sea Anemones" by Daphne Fautin and Gerald Allen, and "Sea Anemones...as a hobby" by U. Erich Friese.

Family Actinidae
Condylactis

Those anemones in the genus Condylactis mostly come from the Western Atlantic Ocean: Florida, Caribbean, and Bermuda to Brazil. They inhabit lagoons and inner reefs and live either singly or in loose groups near and on rocky crevices in depths from the surface to 90 feet (30 m) and have a temperature range of 68 to 79°F (20 - 26°C). Unfortunately these anemones, sometimes commonly called 'Atlantic Pink Tips,' make a poor host or are simply not accepted by clownfishes. In fact, they should not be kept in an aquarium with corals or Pacific anemones as they are quite aggressive and may damage those organisms. They prefer sandy bottoms and are very sensitive to mishandling. It's a low priced anemone and not truly suited for use in the multi-organism environment associated with most reef aquariums. Even though it contains zooxanthellae and is capable of making its own food, it can be hand fed raw fish pieces, shrimp, tubifex worms, and is especially fond of mussel flesh. Two to three feedings per month suffices as it can get quite large, about 20 inches (50 cm). Does well in captivity if it has its own environment.

Rose Anemone

One of the most popular anemones is the Rose Anemone, Entacmaea quadricolor, sometimes also referred to as the Bubbletip or Maroon Anemone, and which hails from the Indo-Pacific and Red Sea. These are photosynthetic anemones that require excellent lighting (PAR 300) and in the wild are sometimes found in dense colonies, usually in shallow clear water reefs where gentle water current (WM 1) exist. Almost always the base (foot) of the animal is securely fastened to a firm surface, often in crevices or between rocks. Colors vary slightly, however, they are usually reddish/orange.

This anemone, depending upon its geographic location, is said to host 13 clownfish species. Red Sea - host to Amphiprion bicinctus. Indian Ocean - host to A. allardi and A. clarkii. Indo-Pacific - host to A. ephippium, A. frenatus, A. melanopus, A. chrysopterus and Premnas biaculeatus. Australia - host to A. akindynos, A. mccullochi and A. rubrocinctus (Schiemer/99). Nevertheless, it's usually utilized in aquaria to host the popular A. ocellaris and A. percula species.

As for its 'sometimes' bubble tipped tentacles, Delbeek and Sprung (1997) believe light intensity is the main factor for its bulbous tips. It has also been said anemonefish coax this odd shaped tentacle end. I've seen both bubbletip and non-bubbletip Rose anemones; therefore, the causes of the bubble tips remain unexplained. And should add, it's hardy and generally very easy to care for and can be maintained with or without anemonefishes.

As to reproduction, it's capable of both sexual and asexual reproduction, yet in aquaria, asexual reproduction usually occurs as longitudinal fission (cloning), and it's quite common for the species to produce many clones of itself within a year or two. Stress of some kind, e.g., too high or low specific gravity or temperatures, and/or too intense lighting, has been said to initiate the cloning process. In the wild, sperm and eggs are released into the water column and after fertilization, develop into larvae. Some survive the ordeals of being 'plankton' and find a safe place to develop.

For initial placement of a specimen in the aquarium, begin by placing it in a very gentle flow area that is well lit, yet not overly intense and preferably next to live rock. It will then no doubt move to an area to its liking and call it home! Once settled in its 'home' area, feed once a week with pieces of shrimp, clam meat, fresh marine and/or fish flesh. Place these morsels close to its central mouth area, and if healthy, its tentacles will do the rest. Keep in mind these anemones can get quite large, more that 15 inches (37.5 cm), therefore they are not suited for nano type aquariums! Also, as previously mentioned, add this species, or in fact any desired anemone prior to adding corals, as they can and will no doubt move themselves to various areas and if going over corals, can injure them. And since these anemones are found in clear water reef areas, aquarium water quality is important, therefore keep its parameters similar to those found in the wild.

Furthermore, do not buy a clownfish and an anemone at the same time. Buy the anemone first and let it settle into the aquarium. After a period of time you can introduce the clownfish. If your goal is to observe a clownfish/anemone relationship, then buy a species of clownfish that is known to associate with bubble-tip anemones. And keep in mind it prefers a krill/shrimp diet


Family Stichodactylidae
Ritteri Anemone

There are quite a few in the genus Heteractis that show up in the trade, but this species remains the most popular. Formerly called Radianthus ritteri and now Heteractis magnifica, its common name has remained as the 'Ritteri' anemone or Purple Base Anemone, and hails from the Indo-Pacific Ocean: Red Sea to Somoa. It inhabits shallow reef and lagoon areas where it is usually home to hundreds of various clownfishes and often found in large colonies at depths of 3 to 30 feet (1 - 10 m).

In the wild, it prefers to have its base attached to rock in open water where there is good water flow (WM 2) and intense light (PAR 300+) to stimulate its symbiotic zooxanthellae. When light is insufficient, it may expand to capture as much light as possible. Conversely, when it is too bright, it will retract to reduce the degree of oxygen production by its symbiotic algae. Excessive oxygen can actually damage the anemone tissue structure. Excessive UV produced by some metal halides may also damage tissue structure. It likes a spot in the aquarium that provides moderately strong current and very good light intensity. Seems to prefer a diet of crustaceans rather than other type meaty foods with five or six monthly feedings recommended. Quite hardy and an excellent host for several clownfish species.

Family Aiptasiidae
Rock/Glass Anemones

After being in the aquarium hobby for over five decades I can say 'been there' and 'done that.' And when looking back I can see some frustrating timeframes. One of the most frustrating was getting rid of unwanted hitchhikers, e.g., Aiptasia anemones that would come in on new corals or live rock.

These anemones, usually the species A. pallida or A. pulchella, are commonly called rock or glass anemones and can obtain 4 inches (10 cm) in height. They can reproduce with alarming speed and their sting will damage most corals and can easily become a plague in many aquariums. Even small fish are in danger, as they will eat them if they become caught in their tentacles. And if not brought under control quickly, these anemones can easily out-compete corals in reef aquariums for space.

They generally spread throughout the aquarium in a couple of different ways. One is via basal laceration where small pieces of tissue protrude from around the foot or base area. These tiny pieces quickly develop into new anemones. Besides basal laceration, tissue fragments from the main structure, possibly from a predator picking on it or the aquarist trying to remove it, also develop into new specimens. Don't you wish it was that easy to propagated desired species? In fact, when conditions are ideal a totally new clone can develop within a few days. Unfortunately, conditions are usually right in almost all closed systems, as nutrient content is often higher than what is found in the wild.

After reading the above on how easily they can spread, crushing them or trying to pry them loose from their moorings can be seen as not a wise approach. And because these pests have become over time a major nuisance in many aquaria, many different approaches have been tried on how to eradicate them. I have personally tried almost all of them and in fact, some are quite unique. Unfortunately have not found a surefire 100% way to rid the entire aquarium, especially in large systems, once these pests have gotten a foothold. In such cases it simply becomes necessary to limit their spread by occasionally introducing known and effective predators.

So what has been tried and what works and doesn't? Good questions, and because eradication falls into two categories - biological controls, and the use of certain chemicals, each should be discussed openly as to what is really effective.

As for biological controls, there are many and some can work in only fish-only tanks and others in reef systems. Among the most successful in my opinion is the use of Caribbean Peppermint Shrimp. These 2.5 inch (6 cm) shrimp have lengthwise lines of red covering a somewhat transparent body. It does not have claws like the Banded Coral Shrimp, however, it's an effective consumer of Aiptasia anemones. In fact, the last time I used Peppermint Shrimp to control these unwanted anemones they were in the aquarium only a few minutes before I saw them heading directly for a small clump of Aiptasia where they quickly devoured them. Other small clumps of anemones simply disappeared over the coming weeks. Yet take note, when their preferred cuisine of Aiptasia disappears, yellow polyp anemones and some species of zoanthus may be on their menu. Past experience with these shrimp have proven very successful in my aquariums. But I have heard not so in some other aquarist tanks. Different strokes for different folks.

Certain butterflyfishes are also an excellent way to rid the aquarium of these pests. Unfortunately many butterflyfishes also dine on various stony and soft coral polyps, feather dusters, and zoanthids. Yet, in fish-only aquariums, the Raccoon Butterflyfish Chaetodon lunula, Klein's Chaetodon kleinii, Saddleback Chaetodon ephippium, Tinker's Chaetodon tinkeri, and Threadfin Chaetodon auriga, or the Copperband Chelmon rostratus are excellent natural predators.

There is also a nudibranch species, Berghia verrucicornis, which is a nocturnal native to the Caribbean and Western Atlantic that only feeds on Aiptasia anemones. In those areas it's probably A. pallida, which is found in mangrove and rubble areas. Juveniles measure about 0.5 inch (1 cm), with adults reaching 1.5 inch (3.5 cm) within a couple of weeks. Of course, once these pest anemones are eliminated, the nudibranch will die since it does not feed upon anything else. The best thing to do in such instances is to pass it along to a fellow aquarist who may have some of these unwanted pests. There is also another nudibranch, B. major, which feeds upon the Pacific Aiptasia species, A. pulchella. There are now many local aquarium shops regularly stocking these nudibranchs because they help keep store tanks free of these pests. And I should add I've tried these nudibranchs and they were quite successful in small tanks when a few were used. However, in huge aquariums it would take an exceptionally large number of these nudibranchs to resolve even a minor problem, as they seem to quickly get lost in the tank. In fact, I put six into a 180 gallon reef tank and a week later could not find one! But the Aiptasia were still there, and then went to Peppermint Shrimp to resolve the problem area.

I've also tried the sting from an Elegance coral Catalaphyllia jardinei and Euphyllia species to kill these anemones. Surprisingly, it really worked! Simply take a small specimen of this stony coral and touch its tentacles to the anemone. However, it was more a nuisance method to accomplish and besides, I dislike wet armpits.

One of the more interesting and widely usable biological controls are Scats (Scatophagidae), which are a brackish and/or freshwater fish. I've tried them with great success in a reef aquarium. Yet I've heard from some aquarists that if they are introduced into an aquarium with a lot of algae, they prefer greens over that of Aiptasia anemones.

Another possibility is the use of a little known Filefish, Acreichthys tomentosus. It is said to be reef safe, yet most Filefish are far from reef safe. Caution is advised if you ever decide to try this species.

As for some chemical controls, they can be used in either fish-only or reef aquariums. Many years ago, when I "had" great patience, I use to inject these anemones with boiling water or a very hot solution of Kalkwasser/Limewater. This would cause the anemone to turn a grayish color, effectively killing the entire specimen. Yet, sticking a needle into the anemone before it could withdraw was almost impossible. I then found by placing the hypodermic syringe needlepoint very close to the anemone and shooting a stream of hot Limewater upon it, that would stun the anemone and prevent it from withdrawing or shrinking in size. It was then fairly easy to get the point of the needle into the still erect body of a fairly large specimen and inject it, killing the darn thing. Again, you must have patience for this sort of thing and like putting your arm into the aquarium.

Another interesting way said to destroy these pests was brought to my attention by a fellow aquarist. He noted that a slush mixture of sea salt deposited directly on the anemone would cause it to immediately die. Simply take some aquarium sea salt, make a slush-like mixture and flow it directly on the anemone. A syringe is a good way of applying this mixture. It can also be flowed into cracks allowing it to reach where these pests may have a foothold. I've tried it with moderate success, again resulting in wet armpits.

Novel approaches such as the use of peppery hot sauce is not recommended, nor are chemicals such as hydrogen peroxide, hydrochloride acid or copper compounds. However, there has been another entry into controlling these pests with a foodstuff that is sprinkled over the anemone. After consuming this material it is said the anemone melts away in about twenty minutes. Readers who have contacted me about this product say it works well and is harmless to other invertebrate. Visit "www.joesjuice.com" for more information. What next "cure" for this pest will be forthcoming would be guesswork, but if anything, I've found the biological methods mentioned above work the best.

Luckily almost all marine aquarists realize that these pest anemones are to be avoided like the plague. But a while back I walked into a shop that was selling Aiptasia anemones! That was "sick" in my opinion. And that's not the first time I've seen this despicable behavior. Hopefully, if you're somewhat new to this hobby, be aware of the inherit danger that exists if this anemone enters your aquarium!

Majano Anemones

This small anemone is in the same 'pest' class as Aiptasia anemones. It's about 1 inch (2.5 cm) in diameter when fully grown and looks similar to a miniature bubbletip anemone, often with club-like tentacles. This Indo-Pacific pest, Anemonia cf. majano, is a hitchhiker that occasionally comes in on live rocks or corals and can reproduce quickly, as do Aiptasia anemones, and sting anything they touch. Natural predators include Centropyge, Apolemichthys, and Pomacanthus Angelfishes, some Butterflyfishes, e.g., the Threadfin Butterfflyfish Chaetodon auriga, the Red Sea Raccoon Butterflyfish Chaetodon fasciatus and the Double-saddle Butterflyfish Chaetodon ulietensis. Unfortunately, these predators of this pest anemone are also a threat to stony and soft corals, making them a potential hazard if placed in a reef aquarium. Possibly the best predator is the Bristle-tail Filefish Acreichthys tomentosus, which hails from the Indo-West Pacific, and is usually found in weedy or seagrass beds. Nevertheless, when majano's run out, the large polyps of some soft corals, such Xenia and those on leather corals, may be on the menu. Therefore, since these are much easier to inject with various killing fluids, as described above for Aiptasia anemones, this might be a more direct path to take in their eradication.

Curleycue/Ringed Anemones

This common anemone, Bartholomea annulata, hails from the Western Atlantic Ocean: Caribbean, Bermuda to the coast of South America and is found singly living in muddy and/or sandy lagoons and bays at depths between 3 to 100 feet (1 - 30 m). They range in size from a few inches (7.5 cm) to a foot (30 cm) in diameter and are a light tan color with white rings surrounding their tentacles. Usually very inexpensive, therefore many new hobbyists are attracted by its price. Unfortunately, they sting and eat both fish and other anemones. The brown color is due to an abundance of zooxanthellae, therefore only fairly good lighting (PAR <200) is required to maintain this animal. It's sometimes a host to a variety of commensal shrimp, yet it's considered to be in the same pest-like group as the Rock Anemone, Aiptasia pallida. They are better kept in an aquarium dedicated to their needs.

Order Coralimorpharia

Family Corallimorphidae
Orange Ball Anemone

This small anemone, which belongs in the genus Corynactis, is sometimes called the 'Orange Ball Anemone' simply because of its tentacle color, yet various colors exist. It's rarely seen in the trade, but due to its attractiveness, becomes a question mark as to its care when available. In the wild, they hail from the Tropical West Pacific, e.g., Philippines, Fiji, and the Solomon Islands and are generally found in dimly lit areas, e.g., under overhangs, as they do not contain zooxanthellae. To survive, they have powerful stinging tentacles to capture prey, e.g., shrimp/small fishes. Its body is almost always brown, while its tentacles usually ball-tipped, can be orange or white, and/or other colors depending upon origin. In the aquarium they need a dimly lit area, gentle water movement (WM 2) and need to be hand fed meaty type foods twice weekly. Caution, they will eat small fishes, so be forewarned!

Families Discosomatidae & Ricordeidae
Mushroom Corals

(Many years ago wrote an article for FAMA magazine titled 'Mushroom Corals - The Corallimorpharians' and in part it's posted on my Articles page with their approval. Nevertheless, also visit my Animal Library where you'll find even more information on these easy to maintain corals.)

These corals are found worldwide with most in shallow tropical waters and because they do better in nutrient rich surroundings and almost all are photosynthetic, they are probably the easiest of all corals to maintain. And with various size and colored disc-shaped polyps they are understandably extremely popular.

Their common names include Disk Anemones, Mushroom Anemones, Elephant Ear Coral, False Coral and of course, Mushroom Coral. Even though the word 'anemone' is used quite frequently to describe them, they are not true anemones, nor are they true corals. But are somewhere in between or more appropriately, a comparative anatomy or simply put, a morph (yet more closely related to scleractinian corals).

Since they all contain zooxanthellae, they can produce the majority of their own food via photosynthesis. However, some also absorb nutrients from the surrounding water and/or trap various substances and bacteria in their mucus coating where it is then moved to its central mouth area. Therefore, most do not have to be handfed, yet iodine additives appear somewhat beneficial. Besides the varieties of colors and textures, their low cost and maintenance requirements make them very popular with most aquarists. (WM 1) (PAR <150)

As to the existing taxonomy information on this group of organisms, it has for a very long time been confusing to say the least. And I've in the past accepted longstanding thoughts as to their classifications since I'm not a scientist. But that all ended in 2003 when revisions by Dr. Vincent Hargreaves resulted in a new rearrangement of this order. It now encompasses 3 families (Corallimorphidae, Discosomatidae, and Ricordeidae) containing 9 genera with 59 species, and is currently shown below. In fact, Dr. Hargreaves worked with the world's leading authority in this field, the late Dr. J. C. den Hartog, when beginning this revision. One of the results of this revision has been the elimination of the family names Actinodiscidae and Sideractidae. Another revision has been that the two genera Nectactis and Sideractis, each with a single species, have now been placed in the family Corallimorphidae. Bear in mind that Dr. Hargreaves revisions encompass two of the three families, and that Dr. Daphne Fautin of the University of Kansas is working on the third family, i.e., Corallimorphidae, which contain the genera Corallimorphus, Corynactis, Nectactis, Pseudocorynactis, and Siderctis. And I should add that the widely used term 'Actinodiscus,' which I have seen used in articles for many years, is not really a valid name!

As of 2015, enormously colorful cultured specimens of Discosoma sanctithomae, now being called called 'Bubble' mushrooms, have entered the marketplace. Selling sometimes for over 1000 dollars 'per' polyp (yes, that's a correct sum of money!), these eye-catching mushrooms have gained the attention of some dedicated hobbyists. For further information, search the Internet for those offering these leading edge specimens.

Also, checkout my website posted article on mushrooms for more information.

Order Zoanthidea
Zoanthids

(Many years ago wrote an article for FAMA magazine titled 'Zoanthids - A Wide Range to Choose From' and in part it's posted on my Articles page with their approval. Nevertheless, also visit my Animal Library where you'll find even more information on these easy to maintain corals.)

Those in the Order Zoanthidea are among some of the reefkeepers' favorite corals. It is comprised of two suborders with each having two families, about 11 genera and about 130 presently described species, with slightly more than that still undescribed! All are somewhat or very difficult to identify, with some requiring internal microscopic examination of tissue segments to properly identify. Nevertheless, most species can be identified down to at least genus level.

As noted by Dr. Vincent Hargreaves, those in the two suborders can be determined by the wall (septal) arrangement around the anemone's throat/sleeve-like structure, technically called 'actinopharynx' that behaves like a valve to retain water inside the polyp. If the fifth septum from the dorsal axis in either direction is short or incomplete, the species belongs to the Brachycnemina suborder. If the fifth septum is long and complete, it belongs to the suborder Macrocnemina. Reproduction is usually by asexual budding at the edges of the colony growth, which can result in colonies encompassing several square meters. Polyps have a single ciliated longitudinal furrow (siphonoglyph) at one end of the slit-formed mouth, which serves to provide water circulation into the gastrovascular cavity. Most species have two tentacle rings, yet some only one ring, and the length of these seems to determine whether the species captures organisms or solely depends on its zooxanthellae for nutritional needs. Sometimes both different feeding species are found together in the same location, possibly providing a symbiotic arrangement to the other. As to those in the family Zoanthidae, probably containing those of most interest to aquarists, they can be divided into three genus groups. Exact species thereafter is often guesswork! There are those where the polyps occur singly and exist embedded in sand, e.g., those in the Sphenopus genus. Those that live in colonies, with or without stolons (lateral connecting structures) or the base tissue/mat/coenenchyme between the polyps, e.g., Isaurus, Protopalythoa, and Zoanthus, are in the second group. However, this group can be further divided - if sand is embedded in the column of the polyp, with or without stolons (lateral connecting structures) or the base tissue/mat/coenenchyme between the polyps, its no doubt a Protopalythoa species. If sand is not embedded in the column, it could be either a species in the Isaurus or Zoanthus genera. And if those polyps are closed during the day, it's a Isaurus species. If open during the day, it's a Zoanthus species, usually with its oral disc having two distinct colors. The third group has polyps deeply set into the coenenchyme and may, at times be totally retracted, e.g., Palythoa.

FYI: My zoo's, especially my green ones, have been bothered by a very small nudibranch, about 5 mm in length that has two brown antennae and a double lengthwise row of green tentacles the exact same color of my green zoanthid. (OK, I know they are not tentacles, but hopefully you get the point!) If not siphoned out when seen, which is difficult at best because of its coloration and size, coral polyps fail to open and begin to dissipate. If experiencing dwindling health of your zoo's, give special attention to visually checking for this unwanted pest. Also, keep in mind the snail, Heliacus areola, (Box Snail) feeds upon zoanthid colonies. It is usually more visible at night when polyps are closed, and should be discarded when seen.

Again, visit the Articles page for 'much more information and photos of these most popular corals!


Subclass Ceriantipatharia

Order Ceriantharia

Family Cerianthidae
Tube Anemones

These are bottom-burrowing anemones and are better maintained under low light (PAR <100) with little water movement (WM 1). Their tube is not built of sand, debris or slime as has been thought for a very long time. Instead, it is almost entirely made up of nematocysts of a special type called ptychocyst (Mariscal et al., 1977). Little is know about their reproduction, yet fission of the body, budding, production of sperm and eggs resulting in planktonic larvae, and live birth have been documented in various species. Since tube anemones are burrowing animals they should be provided with an inert container in the aquarium filled with sand/gravel and sized to easily fit the length and width of their tube. Some species are night animals and only expand their tentacles in the dark. Their outer longer tentacles are used to catch food and transfer it to the shorter inner tentacles, which then transfer the catch to the mouth. Tube anemones should be fed very small pieces of fish, clam, mussel, and/or squid and frequency depends upon their species. Keep in mind tube anemones have the ability to capture and eat small fish and shrimp, therefore, some thought must be given before placing it into a well-stocked aquarium. They are better kept in an aquarium specially dedicated to their needs.

Class Scyphozoa

Order Semaeostomeae
Jellyfish

To bring this 'softy' section of this chapter to a close there are animals called jellyfish or sea jellies, also in the Phylum Cnidaria and in the Class Scyphozoa. Even though the word 'jellyfish' is a misnomer, since they are not a fish or even an invertebrate, but a free-swimming gelatinous zooplankton! Nevertheless, the term has stuck, and even American public aquariums use the term; jellyfish!

There are very few jellyfish that survive in closed systems as they are very sensitive to water quality and require zero ammonia and nitrite levels, with nitrate not above 5 ppm nitrate-N. They are 95% water, have no brain, heart or eyes and absorb oxygen and release carbon dioxide throughout the entire surface of their body. They also have no digestive tract, and food and waste matter pass through the same opening.

Circular water movement is also recommended, and in fact public aquariums utilize specialized tanks called kriesels or pseudo-kriesels that are circular or square tanks that have their interior corners rounded. Water enters in such a way that circular currents are formed, which keep the jellyfish from settling to the bottom, more or less suspended in the water column as most are plankton feeders. For more information, visit Jim Stime's article titled 'The Midwater Zone, which is posted on my 'Articles' page and also visit his www.jelliquarium.com website for an array of information and products concerning these interesting creatures!

Actually, Jim is to be credited with bringing 'jellyfish' keeping to the hobbyist forefront, and as of 2015, there are now many excellent companies offering low cost and simplified enclosures, making 'jellyfish' keeping quite easy for a large segment of the hobby.

Family Cassiopeidae
Upside-Down Jellyfish

These species, Cassiopeia xamachana/andromeda, are found in the Indo-Pacific, Red Sea, Hawaii, and Australia and has temperature range of 72 to 86°F (22 - 30°C). They inhabit lagoons, seagrass beds, sandy and muddy substrates, and mangrove areas. (Often called the Mangrove Jellyfish.) Both above species look quite similar. They contain zooxanthellae, which provides some nutritional supplement, however a well-lit aquarium with moderate water currents along with a generous supply of Artemia nauplii are its basic requirements in captivity. Keep in mind the species contains nematocysts, so contact with the bare skin should be avoided.


Family Ulmaridae
Moon Jellyfish

This species, Aurelia aurita, is found worldwide and has temperature range of 32 to 85°F (0 - 29°C). Their body is coated with a sticky substance and planktonic animals get stuck in that mucus and then slide onto its dangling arms that in turn move them to its mouth. I actually had a few of these that came in on some live rock; yet they only lasted a few days since conditions did not meet their exacting needs.

The Stony Corals

Subclass Hexacorallia

Let me begin here by first recommending the following books - "Indo-Pacific Coral Reef Field Guide" by Dr. Gerald R. Allen & Roger Steens (ISBN 981-00-5687-7); "Baensch Marine Atlas" Vol. 2 (ISBN 1-890087-11-4); and "Marine Invertebrates And Plants of the Living Reef" by Dr. Patrick L. Colin (ISBN 0-86622-875-6). And I should add some of the information related to here comes from 'Aquarium Corals, Selection, Husbandry, and Natural History' by Eric Borneman, and also Julian Sprung's 'Corals: A Quick Reference Guide.' All of these, and the three book set of "Corals of the World" by JEN Veron (ISBN 0-642-32236-8, 0-642-32237-6, and 0-642-32238-4) deserve to be in your aquarium library. As should magazine subscriptions to Tropical Fish Hobbyist; Coral, the Reef & Marine Aquarium Magazine; and in the U.K., Marine Habitat; and Practical Fishkeeping.

Lets now look at the hermatypic reef-building corals, and keep in mind I've selected those I've had experience with and some others that show up in the trade that you may find interesting!

Order Scleractinia
Family Pocilloporidae

There are three genera in this family that have viable species for aquaria, especially reef aquariums. They are Pocillopora, Seriatopora, and Stylophora, all coming from the Indo-Pacific Ocean and Red Sea. Species are usually found close to the surface along reef edges and has a wide degree of variability among colonies. In fact, these photosynthetic stony corals are second to that of Acropora when it comes to reef building.

Pocillopora

Those in this genus generally need excellent water quality, very good water movement (WM 3+) and strong lighting (PAR 600+). Probably P. damicornis, the Cauliflower Coral, also called Brush Coral, Raspberry Coral, Cluster Coral, or Bird's Nest Coral, is the most popular. These corals hail from the Indo-Pacific, and from the Red Sea to Eastern Africa where colonies sometimes reach heights several meter high. Often having either a pink or green coloration, it's a favorite among reef hobbyists. These photosynthetic corals are aggressive and have short one-inch (2.5 cm) sweeper tentacles, and are a fast grower under the right circumstances. Therefore, provide enough distance between it and neighboring corals. It's said to have a short life span in the wild, probably less than eight years (Richmond, 1987, 1988). Captive-bred specimens are much more adaptable to closed systems than specimens from the wild, nevertheless, a coral for the more experienced hobbyist.

Seriatopora

These somewhat thinly branched and thicket-like photosynthetic corals attain heights of about 12 inches (30 cm), and hail from the Indo-Pacific and Red Sea where they are found in a wide variety of locations, e.g., reef crests, sheltered reef slopes, and lagoons. One species especially, S. hystrix, commonly called Birds Nest Coral or Needle Coral, stands out as a favorite among reef keepers because under 'extremely' bright light, it will take on a bright red color. Bright light, at least >6 watts per gallon (PAR 600+), and very good water movement (WM 3 - 4) is required to keep this coral looking its best. Without especially intense light, its coloration fades as shown in the attached photograph. No doubt a coral better maintained by the experienced hobbyist.


Stylophora

These photosynthetic corals hail from the Indo-Pacific where they are often found on reef edges where wave energy is high. They form small clusters with short club-like projections, reaching heights of about 18 inches (45 cm). Common names include Club Finger Coral, Cat's Paw, Cluster Coral, Finger Coral, and Brush Coral, and colors include pink, green, and bluish forms. These photosynthetic corals need 'extremely' strong lighting, e.g., 6 watts per gallon (PAR 600+) to keep their colors and very good water movement (WM 3 - 4). At night it exhibits short sweeper tentacles, about 1 inch (2.5 cm), therefore provide adequate distance between it and neighboring corals. Probably the most popular species is S. pistillata.


Family Acroporidae

There are four genera of interest in this family, Acropora, Anacropora, Astreopora and Montipora, with Acropora and Montipora those of more interest/availability.

Acropora

These photosynthetic corals are the most abundant in the entire world with hundreds of species, and no doubt the most popular in reef aquaria. They are probably the most common and dominating species found in most shallow water reef environments throughout the tropical regions of the world. Growths take many different forms, e.g., branching, cluster, bushy, finger-like, etc., depending upon species and location. Unfortunately, their common names leave much to be desired, as they are often related to shape or color, making it nearly impossible to accurately distinguish some species found in local aquarium shops with certainty.

Their small polyps basically form 'cups' called corallites and cover most of their outer surfaces. These "small polyp stony" (sps) corals (sometimes referred to as "small polyp scleractinian" corals) generally require intense light, e.g., 4 - 6 watts per gallon (varies by species - PAR 300 - 400+), and excellent water flow (WM 2 - 4). Nevertheless, it's always wise to collect as much information as possible on the desired specimen so as to ascertain its environmental needs as to light and water movement before placing it in the aquarium. If not available, place in moderately lit areas with moderate water movement (WM 2 - 3) and observe its on-going condition. If not experiencing new growth or retaining its original coloration, and water quality parameters are sufficient, move to brighter and more forceful water movement areas. Yet do so gradually. Also, be sure there is nothing in the aquarium finding its polyps a tasty morsel. If its polyps are extended fully, yet new white-like growth usually on the tips of branches is not evident, try feeding the polyps some enriched baby brine shrimp, rotifers, and/or other micronutrient products.

Wild caught specimens are somewhat difficult to ship and acclimate, but once established most exhibit rapid growth under the proper circumstances. Captive propagated specimens fair much better as they are already use to aquarium conditions, therefore the chances of success are more likely to occur.

There are far too many reef aquarium favorites to mention here, yet want to mention one of my favorites, A. yongei, which had astounding growth in a past 125 gallon reef aquarium and actually began developing surface "Islands" or what is referred to as "Tabletopping." Best maintained by experienced hobbyists.

For individual species info for those in this family, view the 'Animal Library' and choose 'Corals - Stony.'

Montipora

Another genus in the Family Acroporidae with a large number of photosynthetic species that are circumtropical in distribution, with shapes varying from branching, column-shaped, encrusting, and/or to those forming large plates or whorl's of stepped plates.

There two favorites in the hobby, M. efforescens, and M. digitata. The first species is commonly called Velvet Coral, Encrusting Velvet Coral, Velvet Rock Coral or simply Plate Coral, which is usually tied to its color, such as Orange Plate Coral. These hail from the Indo-West Pacific and Red Sea, including western, northern, and eastern coasts of Australia east to Tahiti, and north to southern Japan. In the wild, these photosynthetic stony corals are usually found in the clear waters along upper reef slopes and reef crests, yet some are occasionally found in lagoons at different depths and where turbid conditions exist. It tends to form massive encrusting and/or plate-like colonies. Generally bright or dark green, yet bluish, brownish, or orange colored specimens are available depending upon area of origin and their depth.

This is an extremely hardy and disease free stony coral. It is also fast growing, therefore needs good water quality and generally intense lighting (PAR 600+) to maintain its coloration. If maintained at lower than recommended light intensity its zooxanthellae, the alga that generates the majority of its food supply, tend to proliferate. Since the animal is trying to photo-adapt to lower light intensities and these alga are brown, colorful specimens tend to turn brown because of the increased numbers of alga cells. This is the case with many shallow water photosynthetic corals if kept at light levels too low.

There is quite a lot of captive-breeding/frag culturing where this genus is concerned, and various specimens of different species are often cultured under 'extreme' high intensity lamps (PAR 1000) to bring out attractive colors. Therefore, it's always wise to ask under what conditions a very colorful cultured specimen was maintained so as to be able to continue its coloration. Otherwise, a very nice orange, green, or purple specimen may slowly turn an ordinary brown in your aquarium!

Care should also be taken as to its position in the aquarium, as this species is basically defenseless against other corals, even those that are not overly aggressive. Moderate to strong water movement (WM 2 - 3) is also recommended, as is an occasional strong wave of water movement to help keep detritus from collecting on its surfaces.

The second, M. digitata, an upward branching photosynthetic coral, also hails from the same locales and has the same environmental needs as the above discussed species. Its commonly called Velvet Finger Montipora, which sometimes includes its color as part of its name, e.g., Blue Finger Montipora. In the wild, when found in shallow reef environments, pink is usually its coloration, yet in even more shallow waters, blue specimens are sometimes found. Coloration in slightly deeper waters result in cream or brown toned specimens.

For individual species info for those in this family and others, view the 'Animal Library' and choose 'Corals - Stony.'


Family Poritidae

There are three genera of interest in this family, i.e., Alveopora, Porites, and Goniopora.

Goniopora

There are several species in this genus, and most hail from the Tropical Indo and Western Pacific Ocean and Red Sea. Usually free-living photosynthetic stony corals and mostly found in protected lagoons that generally have turbid water conditions. Nevertheless, also found on reef flats, lagoon backwaters, muddy bottoms and where sediment collects. Common names include Flowerpot Coral, Daisy Coral, Anemone Coral, and Ball Coral.

They have long stem-like polyps that extend from either a half-moon shaped stony base or from branch-like structures. Color is usually various shades of brown, with pink and green versions occasionally showing up in the trade. Yet, there are many color combinations and no two specimens looking alike. The flower-like polyps can extend far out from the base area, with some specimens extending 18 to 24 inches (45 - 60 cm). On rare occasions, encrusting forms are found. Polyps are extended during day and somewhat retracted at night.

As for maintaining these corals, recommend it being kept in nutrient rich tanks with low to medium light (PAR <200) and gentle water movement (WM 1). And until their nutritional needs are clarified, this may be one of the corals that are probably better left in the wild. And the safest area to place them is on the bottom, as falls from ledges and rock tops will often injure them beyond being able to recover. And note, anemonefish tend to think/use their long stem polyps as an anemone, greatly stressing the coral, usually leading to the demise of the coral! And note, Goniopora is sometimes misidentified as Alveopora. Goniopora have 24 tentacle tips, whereas Alveopora has 12 tentacle tips.

Porites

There are many species in this genus, and all are photosynthetic corals found in many diverse areas throughout the world. Those chosen for aquariums seem to be at their best when given extremely good light (PAR 400+) and high-energy water movement (WM 3 - 4). These corals take many forms, e.g., bolder shape, plate-like, dome-shaped, and stout branch-like growths with blunt ends. Usually brown, yet there are some colorful versions to be found, e.g., yellow, purple, and pink. Common names include Christmas Tree Worm Rock Coral, Boulder Coral, and Encrusting Coral.

My favorite is P. cylindrical, which is sometimes called Yellow Finger Coral, Yellow Cylindrical Coral, Finger Coral, Jeweled Finger Coral, or Cylindrical Porous Coral. It hails from Indo-West Pacific and Western Pacific Ocean. This photosynthetic and phytoplankton feeding branching, column or finger-shaped stony coral is found in shallow waters on upper reef slopes and lagoons where it receives strong water movement and intense light. Colors depend on areas of origin, but light tan/cream, yellow, blue, or green occasionally appear in the market.

Keep in mind they normally/occasionally shed a thin waxy surface layer of mucus to rid themselves of various waste products and algae that might cover their tissue surfaces. This is especially so if the specimen is placed where water movement is inadequate.

Be aware that a small, yellowish-white Nudibranch, Phestilla lugubris feeds upon porites coral. Look for discolored patches of polyps, or polyps not extended for unusual periods of time. If so, then look closely for this tiny nudibranch and remove, probably with a tweezers.

Alveopora

Those in this genus are rarely seen in the trade, but nevertheless one of my favorite corals. Common names of this photosynthetic coral include Ball Coral, Branching Flower Pot Coral, and Daisy Coral. Similar to Goniopora, however its polyps have 12 tentacles and Goniopora has 24, and it forms branching columns. They are normally found in protected turbid environments, and rocky foreshores. I had one specimen, A. gigas, for 7 years in a 20 gallon reef tank lit with two 9W fluorescent lamps and one very small powerhead for water circulation. Now have a specimen located in a nano aquarium where it receives low light (PAR <200) and gentle water movement (WM 1), which appears to be needs that mirror that of the Goniopora species.

For individual species info for those in this family and others, view the 'Animal Library' and choose 'Corals - Stony.'

Family Siderastreidae

There are several genera in this family that consist of shallow water corals that generally form flat to slightly raised/dome-shaped colonies, however they are rarely collected except for Psammocora.

Psammocora

P. contigua is a fairly common photosynthetic stony coral found in the Indo-West Pacific and the Red Sea and usually collected in shallow, sandy reef environments. Massive colonies are often formed having combinations of flattened branches, columns, irregular nodules and/or encrusting areas and forming plate-like structures. Often simply brown to somewhat gray in color, yet occasionally a green or pink to purple tinge specimen shows up in the trade.

Even though rarely seen in the trade, it's a good find as it's easy to maintain as its not overly fussy about water quality, available light (PAR 200), or even that of water movement (WM 1 - 2). In fact, its one of the stony corals that can do very good under average fluorescent or metal halide lighting. And its also a slow grower and makes for the ideal coral to fill in lower areas in reef aquariums.

Even though not overly colorful, this species requires no special care other than not being placed too near aggressive corals. If increased growth is desired, direct feeding during daylight hours when its polyps are visible can be attempted with zooplankton-type products such as rotifers, newly hatch brine shrimp, or Cyclop-eeze.

For more information on this and other species in this family, view the 'Animal Library' and choose 'Corals - Stony.'

Family Agariciidae

There are probably only two genera of interest to hobbyists in this family, Pachyseris and Pavona. Others such as those in the genera Agaricia, Coeloseris, Gardinineroseris and Leptoseris are plating and encrusting corals that are rarely if that, seen in the trade.

Pachyseris

There are several species in this genus, with common names including Phonograph Record Coral, Elephant Skin Coral, Corduroy Coral, Ridge Coral, Castle Coral, Plate Coral, Sheet Coral, and Scroll Coral. They have plate-like and/or mound-like growth and come from the Indo-West Pacific, upper regions of the Red Sea, and Central and Western Pacific, including the northern coasts of Australia where they inhabit shallow lagoons, reef slopes, and surge channels. These photosynthetic corals are often more than a meter across and in height, and their uneven ridged surfaces have no visible polyps or tentacles. Coloration depends upon location, yet usually a bluish-gray or brown, with orange-brown or mildly green specimens occasionally seen in the trade.

Since these species do not have visible polyps, it's evident that photosynthesis and absorption are its primary nutrient sources. However their tissue layer is quite thin and they are susceptible to white-bad disease, which is explained in Chapter 14. Also, specimens kept under less than ideal conditions have the tendency to lose tissue coverings, possibly due to its dependence for its zooxanthellae to provide the majority of its nutritional needs.

One of the more commonly available species, P. rugosa, has heavily pronounced meandering ridges and some vertical columns. And with most specimens coming from shallow water environments, proper location in the aquarium is paramount, as is water chemistry if it is to succeed. Yet when properly located, its an excellent stony coral addition to most reef aquariums as its very hardy and will do well in areas receiving bright light from metal halides or LED's in the range of 4 - 6 watts/gal (PAR 300 - 400). Moderate to strong water movement (WM 2 - 3) directly impacting the specimen helps keep its surfaces areas free of detritus. Since growth occurs quite rapidly under good circumstances it may take on a more plate-like shape with small columns than simply an overall mound-like growth. If so, its wise to give the specimen ample distance from anything that could become shaded. And because its skeleton material is thick and difficult to break once it becomes somewhat massive, it's the neighbors that will have to be moved! Probably better maintained by experienced hobbyists, as its calcium and alkalinity needs are quite demanding.

Pavona

Common names include Cactus Coral, Lettuce Coral, Star Coral, Leaf Coral, and Frilly Coral, and there are many species to choose from in this genus, with all being 'highly' aggressive, so give your choice, usually Pavona cactus, sufficient space from neighboring corals. Most take an upward leafy-like wavy growth.

They hail from the Indo-West Pacific and Red Sea, including western, northern, and eastern coasts of Australia east to Tahiti, and north to southern Japan. These common photosynthetic stony corals, usually brown or greenish brown with white margins, are normally found in lagoons and on upper fringing reef slopes where there is some protection from wave action. As to water quality, they seem to prefer turbid conditions in the wild, and in such areas tend to form massive colonies, often with upright thin contorted frond-like branches with polyps on both sides of the growth.

An extremely hardy stony coral, but does need quite good lighting, with metal halides or LED's preferred in the range of 4 - 6 watts per gallon (PAR 300 - 400). If lighting is sub par, it will influence the physical structure or appearance of the coral, e.g., its wavy plates will grow wider and more pronounced. Also, possible existing green colors will fade and the specimen will become browner in color. As for water movement, (WM 2 - 3) seems to serve it well yet consider occasional strong waves of water movement to keep detritus from collecting on its surfaces.

This is a coral I've never fed, but if increased growth is desired, zooplankton-type foodstuffs such as rotifers, newly hatch brine shrimp, or Cyclop-eeze could be applied over the polyps during daylight hours. This is an easily propagated/fragged species, responding well to placement in various types of putty media for grow-out.

For more information on these and other species in this family, view the 'Animal Library' and choose 'Corals - Stony.'

Family Fungiidae

(As for those of interest as noted below, have written an article titled 'Stony Corals - the Family Fungiidae' for FAMA magazine in 2007 and am posting some of it below with their approval to help describe these very interesting and desirable corals.)

There are basically four genera of interest in this family for reef keepers, Cycloseris, Fungia, Heliofungia, and Herpolitha. Yet some other rarely seen species in some other genera exist.

When some aquarists think of 'stony' corals, they generally place them in the category of 'reef-building' corals, i.e., Hermatypic corals. However, where those in the Family Fungiidae are concerned, most are actually Ahermatypic corals, which are non reef-building free-living stony corals. Additionally, they are mostly solitary animals, i.e., they have one mouth, not numerous mouths, which should they, would technically place them in the colonial category.

There are 13 genera in this family, however, there are some unsettled points of view surrounding some genera/species. Alf Nilsen notes that a specimen called Fungia simplex (Veron, 1986; Hoeksema, 1989), is an exception when it comes to the solitary corals found in the Fungia genus, as it always has multiple mouths. Then there's the thought (Veron, 1986) the genus Ctenactis is a subgenus of Fungia, which should include a questionable genus, Herpetoglossa, which then should include Fungia simplex.

Another interesting aspect is that most juveniles in this family are attached to rock or coral and become detached, i.e., free-living, as they grow larger. Those in the genera Lithophyllon and Podabacia, however, remain fixed and are colonial species, and those in the genus Cantharellus, also remain fixed, but are a solitary species. Also, the related Family Fungiacyathidae contains some azooxanthellate/Hermatypic corals that come from non-reef areas and from very deep water, with one species, Fungiacyathus marenzelleri coming from a depth of over 23,000 feet (6,000 m)! But lets not anguish over these aspects/details, as most of the species in many of these genera are far from being common in the trade. Therefore, lets concentrate on what is important and should be known about the species we often keep in our aquaria.

These hail from the Western and Central Pacific Ocean, Indo-West Pacific regions, and the Red Sea, and some are among the largest of the solitary corals in the world. Most live in fairly shallow waters, e.g., less than 30 feet (10 m), where they are generally found on soft substrates on reef slopes, reef and lagoon flats, and interconnected sandy reef areas that are protected from very strong wave action.

The members of this family 'generally' form saucer-shaped specimens, although some do form elongated specimens, and have a slightly raised central area/dome, presenting convex topsides with a slightly concave bottom area. The domed top serves a good purpose, as it allows for sediments of various types to be easily shed when there is polyp extension and/or its cilia move the coverings downward toward their outer edges. These corals also have a heavy mucus coating that serves two purposes. It can easily reject deposited sediments by sloughing off the mucus and because its mucus contains powerful nematocysts, can either capture food or sting offending corals. Nevertheless, its almost entirely unaffected by the stings from other corals including those within its own family. Tentacles are normally retracted during the day, and extended at night so as to feed upon the increased plankton content during these timeframes.

As for reproduction, there is both separate male and female specimens in some genera, and only hermaphrodite species in other genera. Sexual reproduction happens when eggs and sperm are released into the water. Asexual reproduction occurs when daughter (anthocauli) colonies form from pieces of skeleton and tissue from the parent. There are recorded happenings of asexual reproduction happening in aquariums, (Alf Nilsen, 1989), however, they remain quite rare.

In aquaria, they should be placed on a sandy substrate in areas receiving bright light and moderate water movement (as noted below), and even though photosynthetic, should be fed at least once per week with meaty foodstuffs, e.g., fortified brine shrimp, mysis, products containing Cyclop-eeze, and/or other marine diced/graded meaty foods. Keep in mind some species have short tentacle extension during the day, with further extension occurring in evening hours. Feeding should be at timeframes when tentacles are the most prominent.

Bare in mind these corals are phototaxic (move towards light) and can move (even up a slight grade), up to 12 inches (30 cm) per day. Should they touch another coral other than in their own family, it may generate mucus that could cause severe damage to the species its in contact with. And please, do not place these corals on ledges or rocks where they may fall from and be injured. There four favorites that are almost always available in the trade;

Fungia

There are many species to choose from but none as popular as F. scutaria, commonly called Plate Coral, Mushroom Coral, Disc Coral, or simply Fungia. It hails from Eastern Africa to the Central Pacific Ocean and the Red Sea. This is a solitary and usually saucer-shaped photosynthetic single polyp coral with a slightly raised central dome, and a single central mouth. Since it inhabits fairly shallow soft sand and coral rubble zones it should be cared for as mentioned above. The most common color is green, however other colors or combination of colors are occasionally available, sometimes with varying degrees of purple or red. I've never seen specimens larger than 5 inches (12.5 cm) in the trade, however they can attain at least twice that size in the wild. (PAR 300 and WM 2)


Cycloseris

As to correct species name, C. cf. hexagonalis 'or' C. cf. tenuis it depends upon whom it's discussed with. It has common names such as Plate Coral, Orange Plate Coral, Mushroom Coral, Disc Coral, and Fungia. It hails from the Western and Central Pacific Ocean, Indo-West Pacific Regions and the Red Sea. This photosynthetic stony coral is similar in appearance to Fungia spp., with only a slightly raised central dome and a somewhat flat smooth back. Each disc represents a single polyp having a central mouth and in the wild, inhabits more sandy areas, e.g., soft sandy substrates on interconnected reef areas. These smaller family members, about 2 inches (5 cm), have colors that are usually white, tan, light green, or a yellowish-orange. They also should be placed on a sandy substrate in areas receiving bright light and moderate water movement and cared for as explained above. (PAR 300 and WM 2)

Note that the use of 'cf' - an abbreviation of the Latin word "conferre" meaning to compare, when used in the name of a species suggests the name is tentative, and is being used to compare it to an already known correctly described species. More scientific effort is needed to resolve this issue, but until that time arrives educated guesswork will suffice.

Heliofungia

H. actiniformis hails from the Red Sea, Indo-Pacific Ocean, Philippines, and Micronesia to New Caledonia. Common names include Plate Coral, Long Tentacle Plate Coral, Disk Coral and Mushroom Coral. It's another free-living solitary photosynthetic stony coral found in the same areas as the Fungia species. However, its long anemone-like tentacles are extended during the day and retract at night. Therefore feeding should take place during daylight hours when the tentacles are fully extended. Otherwise their care remains the same as above two species. Comes in various colors, e.g., pink, blue, green, or brown. (PAR 300 and WM 2)


Slipper Coral

Herpolitha limax hails from the Red Sea, Indo-Pacific Ocean, and Eastern Africa, and are also found in similar areas as Fungia corals, however are considered colonial corals as they often have a series of mouths running along the length of their central area. Similar in body height to Fungia coral, however more elongated, hence their names Tongue or Slipper Coral. Sometimes found 'Y' or 'V' shaped, which is caused by regeneration of a damaged area. Although they are normally more 'tongue' shaped. This usually brown colored photosynthetic coral can get quite large, with specimens in the wild attaining a meter in length.

This is a very hardy coral and as with other fungiids, locate them on sandy or course substrate in areas receiving bright light and gentle to moderate water movement (PAR 300 and WM 2). Since they are not aggressive corals, they can touch other corals without inflecting damage, however the same may not be true for the species it is near or touching! Therefore provide sufficient distance between it and possible aggressive corals. Keep in mind this coral is capable of moving by itself, so keep a wary eye as to its location in the aquarium.

Since this is a photosynthetic stony and very capable of generating its own food supply there are no special feeding requirements. Nevertheless small pieces of marine fish/shrimp flesh can occasionally be offered this species and should be placed near its centrally located mouth(s). If this does not trigger a feeding response, remove the offered morsel. Occasional feeding would be once a week, however I've personally found it not necessary to hand feed, as this coral seems to do very well without any special assistance from the hobbyist.

Even though very hardy, water quality is an important issue and recommend keeping calcium and alkalinity parameters within a balanced state, along with the proper level of magnesium in relation to the existing specific gravity.

Even though all of the above are quite hardy and disease resistant, their long term survival in the captive system will not be possible unless there is sufficient open substrate areas for these animals to traverse, and of course attention to its specific nutrition requirements. All in this family are considered good beginner corals.

For more information on these and other species in this family, view the 'Animal Library' and choose 'Corals - Stony.'

Family Oculinidae

Those in the Galaxea genus are mainly the only species of interest in this family.

Galaxea

There are two species in this genus, G. fascicularis and G. astreata, with the latter most often seen in the trade. These are 'aggressive' photosynthetic stony corals that hail from the Indo-Pacific, Red Sea, and Eastern Africa. They are found in reef environments protected from strong wave action where their white-tipped tentacles form encrusting rounded colonies, sometimes exceeding a meter or more in diameter. Its common names include Star Coral, Galaxy Coral, Brittle Coral and/or Crystal Coral and appear in different shades of gray, pink, brown or green.

There are some drawbacks with this coral, as its tissue covering is very thin. Since it's a brittle structure to begin with, damage from collection and shipping often make it difficult for specimens to recuperate from the associated stresses. Often they are victims to brown jelly infections and/or tissue recession. If a specimen is healthy, low water movement (WM 1) and very bright light, 4 - 6 watts per gallon (PAR 300 - 400) is needed to maintain it. If one gets this far, one must take into consideration the long and dangerous sweeper tentacles it extends when the lights go out. They can reach 12 inches (30 cm), sometimes more, and anything downstream is in danger of being stung to death. Occasional daytime feedings of zooplankton, such as enriched adult/baby brine shrimp, appear to hasten growth. Because of its poor history of survival in captivity, I consider this fragile species better suited for the more experienced hobbyist.

Family Mussidae

There are many of interest in this family, e.g., Acanthastrea (Acans), Micromussa, Blastomussa, Cynarina, Lobophyllia, Scolymia. Symphyllia, and others!

Acanthastrea/Micromussa

Two of the more recent genera experiencing growth in the trade are Acanthastrea and Micromussa. They are almost indistinguishable; with those in the Micromussa genus having smaller corallites (the skeletal area containing the polyp) than those in the Acanthastrea genus. Nevertheless their colors are extraordinary, as are their prices, as I've seen small frags (fragments) a few inches (7.5 cm) in diameter costing almost 1000 dollars! In fact, one larger colony was 2000 dollars!

Micromussa specimens come from southern Japan, Hong Kong, and various other Indo-West Pacific regions, with most specimens in the trade now said to come from Australian waters. Technically speaking, they are a fairly new genus of coral, as their species were at one time in the genus Acanthastrea. But as its species numbers increased, those with smaller corallites (8mm or less) were reclassified and placed into a new genus - Micromussa. In the trade they are simply called 'Micros,' and those in the Acanthastrea genus, as 'Acans.' From there, the names of differently colored frags vary immensely, with their names only limited by one's imagination.

As for those in the genus Acanthastrea, they appear to be more widely distributed, with some also found along the East African coastline, Madagascar and the southern portion of the Arabian Peninsula. Presently, most mother colonies in either genus seem to come from Australian or Hong Kong waters. In the wild, these are fairly common corals and are found in shallow protected waters in their regions, with some attaining one or two meters in diameter. They are heavily tissued reef building corals with interconnected corallites of uneven heights having a thick fleshy mantle. Collectors have, in fact, for long in the past simply removed portions of large mother colonies in the wild for the trade so not to flood the market with too many specimens.

Colors vary with origin, yet reds, greens, and various shades of purple with contrasting colors attract hobbyists 'and' high prices. Their availability and wide range of colors has led to an amazing race in the aquaculture trade to produce even more highly attractive specimens. And it may have all started about a decade ago with one species in the Acanthastrea genus, A. lordhowensis, which is naturally found in an array of very pretty color combinations.

As for water parameters, NSW parameters are highly advised, and as for water temperature, a slightly cooler level, e.g., about 75°F (24°C) is recommended. Lighting intensity (PAR 300+) and water movement as (WM 3) is recommended. As to feeding, various meaty foodstuffs so as to get a broad spectrum of vitamins, minerals, and specific coloring agents such as Carotene and Highly Unsaturated Fatty Acids (HUFA's) should be provided to help maintain/provide extra special stunning colors.

Blastomussa

One of the favorite species in this genus is B. wellsi, commonly called the Pineapple Coral, Open Brain Coral, Moon Coral, or simply 'Blasto.' These photosynthetic corals hail from the Western Pacific Ocean, South China Sea north to southern Japan, and the Red Sea where they are usually found on lower reef slopes and in turbid waters. Even though a suspension feeder, it will accept zooplankton/meaty foods when it's feeding tentacles are displayed.

These very hardy, non-aggressive corals form a more mound-like structure, with its fleshy polyps having a diameter of 4 - 5 inches (10 - 12.5 cm), and look quite similar to mushroom corals. The only other species in the genus, B. merleti, has smaller polyps, about one-third the diameter, with each individual polyp forming at the ends of tubular structures that extend outward from a common base.

As to placement in the aquarium, low to moderate water movement (WM 1 - 2) and moderate light (PAR 200 - 300) will suffice. More than these levels of water movement and light intensity seem to inhibit growth! Keep in mind the possible level of aggression from other corals as they can easily damage this species, even mushroom corals can damage it! When feeding the aquarium, if its feeding tentacles (only feed when displayed) are displayed, directly dose the polyps with meaty foodstuffs, e.g., fortified brine shrimp, mysis, products containing Cyclop-eeze, and/or other marine finely diced/graded meaty foods. This is a good beginners coral.

Cynarina

There are two species of interest, both coming from the Indo-Pacific and Red Sea, with each having somewhat confusing common names.

C. deshayesiana, a photosynthetic stony coral, is mostly circular in shape having a single large fleshy polyp. Its common names include Meat Coral, Open Meat Coral, or Knob Coral. In the wild, often inhabit protected reef environments and is sometimes found attached to walls under overhangs. Yet sometimes it's also found free-living on sandy or muddy bottoms. Seems to prefer gentle currents and usually displays its tentacles during the night when plankton is normally more readily available. Many color combinations exist, including those having highly fluorescent colors, e.g., red, orange, pink, and greens.

Seems to be frequently available in the trade because it's easy to collect, and hobbyists like it because it is easy to maintain as its hardy and undemanding.

When it comes to its placement in aquaria, probably the best location is on the bottom substrate where it will receive very gentle water currents (WM 1) and low to moderate light (PAR 200). Keep in mind if water flow is too fast and sand particles continue to cover the specimen, sloughing off these sand particles will cause the coral great stress! And keep in mind they do not like too much direct bright light.

As for feeding, if feeding tentacles are displayed, products containing Cyclop-eeze or similar type products can be directly applied, with one feeding once every two weeks sufficient.

Note: originally described as Carophyllia deshayesiana by Michelin (1850) and later as Acanthophyllia deshayesiana by Wells, (1937), as noted by Sprung in his book tilted "Corals, A Quick Reference Guide." Often misidentified as Scolymia vitiensis.

C. lacrymalis is often called the Button Coral, Meat Coral, Doughnut Coral, Cat's Eye Coral, Owl Eye Coral, or Tooth Coral. This is a mostly circular in shape photosynthetic stony coral with a single large fleshy polyp and almost always attached to hard substrate, usually facing upwards, i.e. not attached to vertical wall areas. Yet inhabits a different environmental-like area in the wild than the species noted above, as it prefers outer reef slopes and drop-offs where water is sometimes quite turbulent.

Its skeleton base is about 4 inches (10 cm) in diameter, yet its single polyp is usually twice that size with its tentacles displayed at night when plankton is more available. Various color combinations exist, with many exhibiting various shades of red and greens, but more common specimens are brown.

As with the above species, it's also frequently available in the trade because it's easy to collect and hobbyists like it because it is easy to maintain as its hardy and undemanding. Yet, it has demonstrated sensitivity to chemicals released by other corals, therefore space between it and other corals should be given some forethought, as even mushroom corals seem to affect it.

As for light requirements, low to moderate light (PAR 200) and moderste water movement (WM 2) will suffice. Since this species is not found on soft substrates, elevate it onto firm substrates/rock, again receiving water movement and light intensity as noted above. As for feeding, it's no different than the species mentioned above. It's also often thought of as a good indicator of water quality since when conditions are excellent there's far greater polyp expansion. A good beginners coral.

Lobophyllia

There is one very popular fairly hardy species among the many in this genus, and that is L. hemprichii. It has many common names, e.g., Meat Coral, Wrinkle Coral, Lobed Brain Coral, Brain Coral, Open Brain Coral, Flat Brain Coral, Red Brain Coral, Modern Coral, or Large Flower Coral. It hails from the Indo-West Pacific and Red Sea, including western, northern, and eastern coasts of Australia east to Tahiti, and north to southern Japan.

In the wild, this photosynthetic stony coral, which prefer clear water areas along somewhat upper reef slopes and fore-reef slopes, is sometimes found in colonies measuring 10 - 40 feet across! Colors vary, with some very nice orange-colored specimens coming from Australia entering the trade lately.

Maintenance requirements differ slightly from the above name genus, as this prefers a water movement slow to moderate (WM 1 - 2), with lighting (PAR 300). Since it can be considered somewhat none aggressive, it can be placed near other corals, yet not downstream from those exhibiting stinging sweeper tentacles. As for feeding, it's no different than the species mentioned above.

Scolymia

There are several species in this genus, with S. australis the more commonly available species (and more expensive due to its colors). Common names include Open Meat Coral, Meat Coral, Button Coral, Cat's Eye Coral, and the list goes on and on, with no doubt the most popular simply being 'Australian Scoly.'

They hail mainly from Australia (Great Barrier Reef and along southern coastline) - other locations in the Central Western Pacific are unproven.

These usually solitary free-living highly attractive saucer-shaped photosynthetic stony corals generally inhabit shallow fore reefs to deeper areas where they are often found on slopes in protected highly clear waters, sometimes under or near overhangs in surrounding areas. Colors include amazing combinations of fluorescent reds, orange and greens!

These extremely colorful, large fleshy polyp corals are always demanding a high price! Since they are collected in areas having different levels of light intensity, some experimentation may be needed as to placement before deciding upon a permanent location in the aquarium. Nevertheless, a fairly bright area preferably lit with metal halides or LED lamps should initially be chosen. The placement area should be flat, and large enough to safely contain the entire width of the polyp, which expands greatly during the day. Ledges are always problematic; therefore recommend placing it on the sandbed surface where it will be impacted with a gentle to moderate water flow. Strong flows will harm the animal. Even though not an aggressive species, be sure to provide enough space between it and its neighbors, as stings, even minor stings from aggressive corals will cause it to shrink greatly, not take offered foods, and waste away.

The specimen in the photo in my aquarium is fed once every three days. Once it senses food entering the aquarium, a ring of feeding tentacles is displayed and meaty foods such as pieces of fish or shrimp flesh and/or mysis are placed directly on the center of the polyp and are then quickly engulfed. Also, occasionally various pellet-like foods are use, as is live foods such as enriched live brine shrimp. But I must say, this species should not be overfed, especially pellet foods, as it will expel the soft excesses in a burst from the central mouth area. I've seen it do this twice, - an odd happening as it seems to spit out the excess, then look poorly for a day or two. And such behavior does nothing to help maintain the surrounding water quality! I use freeze-dried krill, which is rubbed between my fingers in the aquarium water, to encourage many of my corals to put forth their feeding tentacles.

A moderate varied diet has put one additional inch (2.5 cm) growth on the width of this specimen in its first 4 months in my aquarium! Again, overfeeding does cause a day or two decline in the specimens overall condition, so be forewarned - feed in moderation.

This is a hardy, disease resistant coral. (PAR 300 and WM 2)

Family Merulinidae

There are several genera in this family, but that of Hydnophora contains a couple of photosynthetic species that are somewhat common in the trade.

Hydnophora

H. rigida hails from the Indo-Pacific and Eastern Africa, where it's found in shallow lagoons, often in murky and protected waters where it forms a thin, yet angular-branched colony. In the wild its polyps are extended at night, however just the opposite is true in captivity. A second species hailing from the same locales, H. exesa, is also sometimes seen in the trade yet exhibits a more compact growth, e.g., often a more encrusting growth with short branches.

Their common names include Velvet Horn Coral, Horn Coral, and/or Knob Coral. Colors are normally cream or green, sometimes with a green fluorescence associated with some specimens making them highly attractive to hobbyists. But be forewarned, they are "quite" aggressive corals and can deliver powerful stings with sweeper tentacles and/or attacks involving acrorhagi or mesenterial filaments to anything very nearby or that it touches. And it will win all these battles!

Besides proper spacing they need moderate to bright light (PAR 300) and moderate water movement (WM 2). They can also be hand fed phytoplankton and zooplankton foods, which will encourage growth. But keep in mind their aggressiveness; therefore give some thought to its neighbors, especially those that might be touched when its growth becomes larger. Also keep in mind that inadequate light will often cause bleaching and/or brown jelly infestations. Not a good choice for beginners in my opinion, nevertheless if given the proper environmental conditions they are hardy and easy to maintain.

Family Faviidae

This large family, containing 25 genera, is the second largest family of stony (scleractinians) corals behind that of Acroporids. Those in these genera are among the most widely and uniformly distributed corals in the world as they are commonly found throughout the Indo-West Pacific, with a Favia species, F. fragum also found in the Eastern Atlantic, Brazilian region and the Caribbean. Colors vary greatly with origin, and different combinations of yellow, red, green, brown, cream, and purple are often available in the trade.

And most are hardy corals, often found in areas where water quality is less than ideal, therefore seemly ideal for aquarium purposes and therefore can be considered good beginner corals.

Caulastrea

There are a few species in this genus, with C. furcata, having the common names Torch Coral, Column Brain Coral, Trumpet Coral, Bullseye Coral, Cat's Eye Coral, and Candy Cane Coral, the most popular. In general, they are distributed from eastern Africa to the south Central Pacific Ocean, and from the Indian Ocean to Japan. This branching photosynthetic Large Polyp Stony (LPS) coral has single polyps at the end of each branch. In the wild they are found on shallow reef slopes, lagoons, and sandy bottom areas where there is reduced wave action, yet fairly bright light.

Daytime polyp expansion benefits the gathering of light to power photosynthesis, yet during the night, polyps contract somewhat and tentacles appear along their outer edge to catch plankton prey. They do well under moderate light, about 3 watts per gallon, (PAR <300) and moderate water movement (WM 2) and can be feed directly with zooplankton foods when feeding tentacles are visible.

As for colors, the more common species has polyps with a green center surrounded by a brown outer ring, sometimes with white radial lines. Personal experience with this coral has shown the green polyp species easier than the red polyp species to maintain, and therefore make a good beginner coral.

Diploastrea

There is only one species in this genus, D. helipora, and it hails from the Western Pacific, Indo-West Pacific, and the Red Sea. It's found in shallow reef environments, usually on upper protected reef slopes having wave swells or current flow, where it forms encrusting large flat to dome shaped mounds, often several meters in diameter. Usually a brown, tan, or gray, yet green specimens are found, yet mostly in Western Samoa. Its most common name is simply "Moon Coral" but the name "Pimple Coral" has also been seen, and there are no doubt others. Nevertheless, its easily identified as it has tiny volcano-shaped corallites with ribbed sidewalls.

Polyps are normally extended only at night. In the wild, it's often a place for small gobies to gather and await the flow of zooplankton. This photosynthetic stony coral seems quite able to adapt to changes in environments, i.e., various light intensities and water flows, therefore is quite easy to maintain. Undemanding, yet rarely seen in the trade. (PAR 400+) (WM 3)

Favia & Favites

(Many years ago wrote an article for FAMA magazine titled 'Fabulous Favia & Favites Corals' and in part it's posted here with their approval. Nevertheless, also visit my Animal Library where you'll find even more information on these easy to maintain corals.)

Those in these genera are among the most widely and uniformly distributed corals in the world as they are commonly found throughout the Indo-West Pacific, with a Favia species, F. fragum also found in the Eastern Atlantic, Brazilian region and the Caribbean. Colors vary greatly with origin, and different combinations of yellow, red, green, brown, cream, and purple are often available in the trade.

Most are massive, domed or round in shape. Yet geographical differences, e.g., depth, current, and local nutrient levels make individual species identification almost impossible by hobbyists, as the exact same species from a different location can have different colors and shape. To somewhat help with species identification, the Favia genus was divided into three groups according to their corallite size (the skeletal area containing the polyp). In fact, that's similar to what occurred when the Acanthastrea genus was incurring numerous new species and was divided with smaller corallite species placed into a 'new' Micromussa genus.

There are three corallite size divisions in the genus Favia, with those in 'Group 1' having corallites less than 8 mm in diameter. Group 2 has those averaging 8 - 12 mm, and those in Group 3 more than 12 mm. Those in the Favites genus were also divided into groups, e.g., those with less than 6 mm placed into Group 1. Those averaging 6 - 10 mm placed into Group 2; those with 10 - 14 mm corallites into Group 3, and those over 14 mm into Group 4. Even with all these subdivisions, its still necessary in most cases to await the retraction of the fleshy mantle/polyp so corallite size is more apparent before any species identification is attempted. Except for the 'experts,' most exact species identification, at least in my opinion, is still mostly guesswork.

Where hobbyists are concerned, there has been some confusion between the two genera as to which genus a specimen may belong. But if one looks closely, those in the Favia genus have separate corallites whereas those in the Favites genus share their corallite walls with other corallites. Another distinguishing aspect is Favia polyps are sometimes seen as figure-8 shapes, as they are dividing, whereas those on Favites are forming totally separate corallites usually in the area around the circumference of the coral. Favites also have higher corallites than those associated with Favia species and tend to be more uneven in height.

Exact species identification is always helpful, as the selected specimen's placement in the aquarium should be similar to its natural habitat if at all possible. Yet few are ever properly/exactly identified in the trade and are usually sold labeled as: Moon Coral, Brain Coral, Pineapple Coral, Crater Coral, Star Coral, Closed Brain Coral, and Honeycomb Coral to mention just some of their common names. Others are simply labeled a 'Favia sp./ or 'Favites sp.' Unfortunately that tells one little as to their status in the wild. But if one applies the corallite structure as mentioned above, the specimen can possibly be placed into at least one or the other genera and perhaps narrowed to an exact species. From there it can be found what the specimen endures in the wild, e.g., what depth its usually found at, its location of the reef, water movement/current aspects, and other surrounding conditions. Books, e.g., Corals of the World will help narrow their exact identification and provide some of those aspects (See References).

If exact identification is not possible, take into consideration many are found on protected upper reef slopes at depths between 20 - 35 feet (6 - 10 m). This tends to indicate that gentle to moderate water movement (WM 2 - 3) and moderate to bright light are required to maintain them in aquaria. Keep in mind overly strong water movement will prevent polyps from extending, and/or cause tissue recession possibly allowing a microalgae such as 'Ostreobium' to infest its barren skeleton, hastening tissue recession. As for lighting, metal halides/LED's (14 - 20K) may be a better choice than fluorescents, with the range of 4 - 6 watts per gallon sufficing nicely (PAR 300 - 400). In well-lit aquariums, consider locating new specimens somewhat low in the aquarium to first allow them to become accustomed to their new surroundings, and then if desired after a week or two moved to more brightly lit areas. Nevertheless, these corals will do almost as good under fluorescents if supplied adequate intensity and spectrum, yet growth seems to stagnate in those maintained at lower light levels.

All species in both genera are quite hardy, however, they are aggressive, distributing stinging sweeper tentacles at nighttime. Spacing between neighboring corals, especially those downstream, must be given some thought before placing them in the aquarium. On the other side of the coin so to speak, there are some animals that may cause them damage, such as various fish species in the genus Centropyge, which are normally a watch item, as some, especially Flame Angels have a record of picking on clams and some corals. Then there are shrimp, such as those in the genus Saron and Rhynchocinetes, which can't be fully trusted with many corals.

Even though these are photosynthetic corals and under the proper lighting conditions are able to supply their own nutritional needs, additional spot feeding can encourage growth and coloration. On the other hand, if under inadequate lighting, then direct feeding once or twice a week 'is' necessary with meaty foodstuffs made from a variety of different foodstuffs, e.g., scallops, krill, rotifers, copepods, baby brine shrimp, and mysis shrimp.

Interesting, yet still somewhat not fully understood, is their ability to fluoresce under actinic/UV light, as do some other coral species. Recently, its was put forth that the fluorescence of some corals is an attraction mechanism being utilized to gather free floating zooxanthellae alga, since its attracted to 'green' light (Discover Magazine, March/09). Whatever its purpose, some species in both genera radiate extremely colorful patterns under actinic lighting, simply another plus for hobbyists when maintaining these corals.

Now that I'm though the 'generalities' concerning those in these two genera, what specific species are causing increased attention in the trade? Good question, and again, any with eye-catching colors would be the answer and there are several, - F. pallida; F. speciosa; F. helianthoides; F. favus; F. leptophylla; F. lizardensis; and F. rotundata are the most sort after in the Favia genus by the aquaculture industry. Other species are occasionally available, such as F. matthaii and F. stelligera, yet they are not as attractive as the others. As for Favites, there are some highly interesting and colorful specimens available, sometimes commonly called 'Honeycomb' corals because of the shape of their corallites. Several species are available from time to time, e.g., F. pentagona; F. bestae; F. chinensis; F. abdita; F. complanata; and, F. vasta.

One further point to keep in mind, - even though these corals are extremely common in the world, some say their collection will not endanger them. That might be true for those species not overly colorful, but those that are highly attractive are in danger because collectors target them. This is the reason why thoughtful aquarium hobbyists must support the aquaculture/mariculture industry by purchasing captive generated specimens, as the hobby you save - is 'your' hobby.

As mentioned above, these are hardy corals, often found in areas where water quality is less than ideal, therefore seemly ideal for aquarium purposes and therefore can be considered good beginner corals.


Platygyra

The species P. daedalea and P. lamellina hail from the Indo-Pacific and Red Sea and have common names such as Brain Coral, Maze Coral, Ridge Coral, Closed Brain Coral, and Boulder Brain Coral. As previously mentioned, these fairly common photosynthetic stony corals tend to form massive mounds and/or dome-shaped colonies, and are mostly found on reef flats and backwater areas. Colors vary depending upon area of origin, with shades of green, pink, gray, cream or white presenting eye-catching contrasting differences between areas on the tissue surface.

As to the difference between the two species, P. daedalea has ridges more rounded than P. lamellina. Both are hardy specimens and can be placed in areas with moderate to bright light, i.e., 4 - 6 watts/gal (PAR 300 - 400) and moderate water movement (WM 2). Even under varying amounts of light it tends to keep its coloration!

Keep in mind it seems to be quite active during nighttime hours with development of sweeper tentacles, therefore, allow sufficient space between it and neighboring corals. Feeding tentacles are displayed in evening hours.

And even though this is a fairly fast growing coral, direct feeding during evening hours with rotifers, newly hatch brine shrimp or zooplankton-type products will enhance the growth rate! Also, this coral when disturbed/touched will generate copious amounts of mucus that can injure other corals in the aquarium so be prepared to siphon out the mucus if produced.

Family Pectiniidae

There are probably only two genera of interest in this family, each having one species that aquarists commonly see in the trade.

Echinophyllia

This fairly common photosynthetic stony coral, E. aspera is found in most reef environments, especially on lower reef slopes and fringing reef areas in the Indo-West Pacific and Red Sea. It tends to form encrusting plates and folds, with its surface having rounded ridges with its corallites slightly raised and warty looking in appearance. Depending upon location the species can be brown, green, or shades of red and/or orange. Common names include Plate Coral, Scroll Coral, Chalice Coral, and Flat Lettuce Coral

I've found this coral difficult to identify and have depended on the shops shipment list or knowledge that the specimen was directly from a wholesaler that guaranteed its genus/species. In fact, the species in the photo was specifically ordered as this particular genus and species directly from a collector! Basically, this is a hardy coral requiring moderate to bright light (PAR 300 - 400) and moderate water movement (WM 2 - 3) to remain healthy. I've found it to maintain its coloration under varying amounts of light in the aquarium

Even though I've seen comments saying this species can develop sweeper tentacles and be quite aggressive, I've not seen them. Have also seen statements this species is capable of chemical aggression to its downstream neighbors, but have not seen or heard of defined cases of that either. Nevertheless, recommend it be maintained with small amounts of activated carbon in the system.

This is a photosynthetic coral that seems to do well without direct feeding. Yet recommend keeping NSW parameters within a balanced state, as its growth rate seems quite extraordinary when calcium, alkalinity, and magnesium are in a balanced state. Recommend this species be maintained by more experienced hobbyists, as maintaining seawater quality seems to be highly important for this species.

Mycedium

The species M. elephantotus hails from the Indo-Pacific, Red Sea and Western Pacific and as far east as Tahiti. Its common names include Plate Coral, Green-eyed Cup Coral, Elephant Nose Coral and Peacock Coral.

In the wild, it's found in wave protected shallow fore reefs and as to deeper locations, found there in plate-like mounds sometimes overhanging the edges of drop-offs. Colors vary, as does the size of its corallites (bumps), as shallow water specimens tend to have brighter colors, e.g., green, whereas deeper specimens are somewhat brown/gray, and some have colored margins depending upon their location in the wild.

Because this hardy photosynthetic stony coral is collected in different areas/depths, some experimentation is necessary as to final placement in the aquarium. I have found it best to finally locate it in areas receiving fairly intense light, (PAR 300+) and incurring moderate water movement (WM 2) so as to keep its plat-like structure clear of detritus. And if at all possible tilt the specimen somewhat to replicate its often-found position in the wild. And keep in mind it will extend feeder and sweeper tentacles at nighttime, therefore provide sufficient space, at least several inches between it and its downstream neighbor. However more is desirable, as this hardy encrusting coral can grow fairly large, e.g., several meters across in the wild! One further thought as to placement, its thought to generate a toxin that damages downstream closely located corals.

Direct feeding is only possible when its feeding tentacles are visible, and to get this to happen during daylight hours I have taken freeze-dried krill and rubbed it between my fingers in the aquarium water. This seems to encourage this coral to put forth its feeding tentacles (have tried this with other corals and seems to work well) and feeding various meaty type foods/zooplankton becomes possible. A fairly good coral for the beginner.

Family Trachyphylliidae

There's basically only one species of interest in this small family: Trachyphyllia geofroyi, nevertheless, a second - T. radiata (Wellsophyllia radiata), is considered a variation of T. geofroyi and no longer officially recognized as a separate species.

Trachyphyllia

This extremely hardy photosynthetic coral is found on reef slopes, protected shallow bays, and muddy lagoon bottom areas throughout the Tropical Indo-Pacific and Red Sea where it prefers gentle water flow and moderate lighting. Initially, while quite immature it's attached to hard substrates of various kinds and as it grows in weight and size, breaks free and becomes a free-living coral.

Often found in various color combinations, including highly fluorescent colors, e.g., red, pink, green, and blue. Red specimens usually come from deeper/turbid water, yet will adapt to varying degrees of light intensity in the aquarium. They are low on the list of aggressive corals, as they do not have sweeper tentacles. As with other fleshy corals living near or on muddy sediment surfaces, they can expand enough to slough off accumulating sediment or have a greater surface area to gather light.

These corals are common in the trade and easy to maintain in aquariums if placed in the correction location. This would be an area that receives gentle water flow (WM 1 - 2) and moderate light, about 3 watts per gallon (PAR 200). Those that are red in color should be placed in shady areas (PAR <100) or at least those receiving some indirect light. Green, tan or brown varieties seem to prefer slightly more light and should be placed in areas receiving low to moderate direct light (PAR 200+). Its also important not to place them where disturbed sand or debris would collect on their surface, since it would then require much energy to slough off that collecting debris. In fact, if it has to continuously slough off sediment it may become weakened and die.

As for feeding, one a week is sufficient and foods such as fortified brine shrimp, mysis, rotifers, and/or products containing Cyclop-eeze are excellent. And for what is worth, reports have surfaced saying this species does not do good in aquariums containing Sinularia species, possibly because of the chemicals that species is said to extrude. Yet I have not seen any problems in my aquariums where both have existed. Bottom line, this is a hardy stony coral and a good beginners coral.

Family Euphyllidae

There are many genera in this family, some with very good reef aquarium species, e.g., the Elegance Coral in the Genus Catalaphyllia, some Euphyllia species, and an interesting species called Octopus Coral, Pearl Coral, or Grape Coral in the genus Physogyra, and lets not forget the very popular Bubble Coral!

Catalaphyllia

Even though C. jardinei is widely known as the 'Elegance Coral,' I've seen other common names applied such as Wonder Coral and Elegant Coral. It has generally been considered one of the most popular, most sturdy and easiest of all photosynthetic LPS corals to maintain. Yet over the past several years, the majority entering the trade has met with failure. Therefore some controversy has arisen as to what areas in the world seem to have the healthiest specimens, i.e., those from the Western Pacific or Australia. That's still unresolved, yet invasive organisms in collector stations may be a contributing cause, and if so, possibly Australian specimens that are thought to undergo more direct paths to the US mainland may be the better choice. (See treatment below)

This Tropical Indo-Pacific species is usually found in protected reef waters, usually in turbid areas. This multi-mouth single polyp animal almost always has extended and free flowing tentacles, almost appearing anemone-like. Some specimens have pink tipped tentacles and others white or purple tips. The large fleshy polyp, sometimes reaching more than 20 inches (50 cm) in diameter, is usually various shades of intense green, which is the pigment that provides ultraviolet protection. Even though found in a variety of shapes and colors, they all belong to a single species. Most these days seem to come from Indonesia, however their distribution is over a much larger area.

In nature they are found in a wide assortment of environments, e.g., mud and/or sandy substrates/lagoons, seagrass beds, deep reef slopes, muddy banks, etc., with their skeleton deeply imbedded in the sediment. Since they normally reside in turbid waters they should not be placed directly under very strong light and suggest the following as an ideal light value (PAR <200) in the aquarium. In fact, they tolerate high levels of nitrate (15 - 35 ppm) as they often come from turbid areas. They also prefer moderate water circulation (WM 1 - 2) and will take occasional hand feedings of meaty/zooplankton foodstuffs.

They are aggressive as their tentacles are covered with thousands of stinging cells called cnidocytes. These cells have a mechanism called a nematocyst (something like a harpoon), which is used to inject poison into anything that threatens or is considered food. Therefore they require a lot of space in the aquarium. In fact, some aquarists may experience an allergic reaction to their sting. And if clownfish are kept in the aquarium, they may adopt this coral as a substitute for an anemone, thereby causing it much stress. Recommend not housing both in the same aquarium, and additionally suggest considering this a coral for the more experienced hobbyist.

As for treating newly received specimens, Julian Sprung advocates treating them with Doxycyline in a quarantine tank or holding tank with strong aeration for possible pathogenic bacteria. He suggests using a concentration of 10 mg/gallon and not illuminating, as the product is photosensitive. He recommends holding them in this solution for three days, then removing and placing them in the display aquarium. He also notes treatment can be used in a display system, but mentions to first shut down the protein skimmer for 48 hours because the product makes it foam excessively. The water may become brown colored after 24 hours, however, it can be cleared with activated carbon. He also says that Nitrofurazone, at 25 to 50 mg/gallon in a bare holding system is also a possible treatment, and to maintain it there for three days before removing and moving to the show aquarium.

Euphyllia

There are of course many stony corals of interest to reef hobbyists, and some of the most popular appear in the genus Euphyllia, where there are thought to be 7 species. Nevertheless, only 3 commonly show up in the trade, e.g., E. ancora called Hammer or Anchor Coral; E. divisa called Frogspawn, Wall Coral, or Zig-Zag; and, E. glabrescens called Torch Coral.

The seven described species fall into two species groups. One forming 'phaceloid' colonies (branching corallites), consisting of the species E. glabrescens, E. cristata, E. paradivisa, E. parancora, and E. paraglabrescens. The second group forms 'flabello-meandroid' colonies (wavy/wall-like skeleton topped by the corallites), and includes E. divisa, E. ancora and possibly E. yaeyamaensis if that remains a valid species.

In the wild, they are often found in lagoons with muddy substrates and turbid water, with E. ancora and E. divisa coming from the Western Pacific region, and E. glabrescens coming from the Indo-West-Pacific including the Red Sea and Eastern Africa.

Both E. ancora and E. parancora have similar shaped long tentacles tipped with a T-shaped projection similar to Thor's hammer, thus the common name 'Hammer Corals' or 'Anchor Corals.' They come in various shades of brown and green with their tips often pink, white, and sometimes blue. Nevertheless, their skeleton formation is quite different, with E. ancora forming a curved wall-like structure, and E. parancora having a branching skeleton.

The 'Frogspawn' termed species consists of E. divisa and E. paradivisa, with the first forming a meandering wall-like skeleton, and sometimes referred as 'Wall' or 'Zig-Zag Coral.' The second forms a branching structure, yet both have long tentacles that are usually brown or sometimes fluorescent green, and end with what looks like clumps of frog's eggs or bulbous projections, hence their common name - Frogspawn.

The third common species, the branching E. glabrescens, is known as 'Torch Coral' and does not have sweeper tentacles, yet do have copious amounts of long tentacles which can do damage to any neighbor that it touches. It has a simple looking rounded little tip in usually a light tan or green color.

All are quite attractive and in the wild can grow into large colonies with some exceeding 2 or 3 meters in diameter. Even though they are easy to maintain in most aquaria, there are some drawbacks that should be taken into consideration before acquiring them.

Fortunately for most aquarists these species come from an array of environmentally different locations, and their water quality and environmental needs are quite easy to provide, e.g., medium light intensity 2 - 4 watts per gallon (will do well under either indirect metal halide or fluorescent/LED's (PAR <300), gentle to medium water circulation (WM 1 - 2) and accept a wide range of water quality parameters. Under the right circumstances their colonies can easily get quite large, e.g., well over 12 inches (30 cm) in diameter. Simply breaking off a single branch and cementing it elsewhere in the aquarium can easily propagate a branching species.

They also contain zooxanthellae and in the presence of quality light these corals are capable of photosynthesizing and producing an adequate supply of its own foodstuffs. Occasional feeding with enriched brine shrimp, or other meaty/zooplankton foodstuffs is feasible and increased growth will result. They all have stinging cells known as nematocysts on their tentacles that allow it to capture small prey as foodstuffs or defend themselves from potential predators.

On the downside, beside their long potent tentacles, Anchor and Frogspawn have what is termed 'sweeper' tentacles that extend at night far beyond their body mass and can sting nearby corals. Yet they can touch each other without doing any harm to their own members.

And since they are collected in the wild by breaking or sawing off pieces of the original colony, then endure long and hazardous shipping trips accompanied by very poor water quality they often arrive in poor shape. Sometimes they come into shops with brown-jelly infestations or receding tissue areas, sometimes with an alga growth already on the exposed skeleton surface. Depending upon the intensity of a brown-jelly infestation, the specimen can be dipped in freshwater, same temperature and pH as the aquarium for one minute, and then placed in a holding/hospital tank until it recovers. Or, if a branching specimen, the more healthy branches removed and relocated to a healthy environment. However, there is no cure for an alga infestation in and on exposed skeleton and specimens having such should be avoided.

I've also seen E. divisa and E. ancora being accepted as an anemone by some clownfishes. In large coral colonies this disturbance usually results in no harm to the coral. But in small specimens, it seems to annoy the coral, thereby opening a window of opportunity for bacteria/fungal infections. Without a doubt, these commonly available species in the genus Euphyllia are quite attractive, easy to maintain, and usually priced quite reasonably, therefore make good additions to most reef aquariums.

Nemenzophyllia - Fox Coral

There is but one species in this genus, N. turbida, which hails from the Western Pacific, however only somewhat common in the trade. In the wild it's usually found in turbid or sheltered reef environments, often under overhangs. Its common names include Fox Coral, Jasmine Coral, and Ridge Coral.

The walls of its skeleton are wavy in shape, extremely thin and topped with large fleshy polyps, almost similar looking as those on the Elegance Coral described above yet smaller. This is a photosynthetic, non-aggressive coral requiring medium indirect light, about 2 - 3 watts per gallon (PAR 200) and gentle water movement (WM 1). Since it does not develop feeding tentacles, direct feeding is not advisable. The most important aspects in its keeping is very gentle water movement and low to moderate lighting, with fluorescent lamps seemly a better choice than metal halides or LED's. When available, a good choice if properly located in the aquarium for the beginner.

Bubble Coral

Bubble Corals hail from the Western and Indo-Pacific Oceans and also the Red Sea, and are in the Phylum Cnidaria (Stony Coral), Order Scleractinia, Family Caryophylliidae, and are in the Genus Plerogyra, pronounced 'Plee-roh-jai-uh.'

They are usually found in protected shaded areas that receive gentle water movement. In these areas, e.g., lower reef slopes, under overhangs and cave walls, they are often found in a vertical position. And when found in moderately lit areas, the waters are sometimes quite murky/turbid.

Its skeleton develops a somewhat flattened, yet continuous and unbranched wall of fused vertical plates (septa). It is topped with a tissue mass that has water filled bubble-shaped polyps, which can develop slightly different shapes and colors. Surface areas of the bubbles contain zooxanthellae and the bubbles expand during the day and mostly retract at night. At night, the coral displays long sweeper tentacles, sometimes 3 or 4 inches (7.5 - 10 cm) in length or longer that can sting downstream neighbors within reach. They are also capable of stinging human flesh, so be forewarned.

Bubbles are usually .5 to 1.0 inch (1 - 2.5 cm) in length, sometimes larger. Tapered feeding tentacles emerge at night to capture plankton. It should be noted the short tentacles associated with the bubbles during the day do not contain stinging cells, yet the sweepers extended during the night do contain stinging nematocysts. Specimens over 3 feet (1 m) across have been seen in the wild.

Where most aquarists are concerned, there is only one species of interest - Plerogyra sinuosa (Dana, 1846). The most common colors are white or light tan, yet some specimens exhibit a pale green or pink tinge depending upon area of origin. Those with colored tints appear to require slightly better lighting than white or tan specimens. Some bubbles have a fingerprint pattern on their surface, or exhibit a shimmering band down the middle surface area of the bubble and these are called Cat Eye Bubble Corals.

It's thought the size of the bubble regulates the amount of light its zooxanthellae receive, since this coral does not photoadapt, i.e., adjusts its level of photosynthetic cells to match light intensity. It simply regulates how much light it sees with bubble size. Therefore proper placement in the aquarium is extremely important. Generally, most prefer low to medium light, such as from fluorescent lamps. (PAR 200) I would not recommend 'strong' direct light from metal halide lamps. And, since its impossible to know exactly the lighting conditions from where the coral was collected, and the fact it has had inadequate lighting during shipment, its always wise to first place it in your aquarium in a low light area. This prevents 'light shock,' which could cause the loss of the coral. Then, as it adapts over the coming weeks, move it to a brighter area if so desired. Just keep in mind, haste makes waste when moving these corals too fast to much brighter areas.

Even though bubble corals are a photosynthetic stony coral, its also a suspension feeder and accepts zooplankton/meaty type foods when its feeding tentacles are displayed. When I feed my aquarium, if feeding tentacles are displayed, I use a small turkey baster and directly dose the polyps/tentacles with meaty foodstuffs, e.g., fortified brine shrimp, mysis, rotifers, diced clam/marine fish flesh/shrimp flesh, and/or products containing Cyclop-eeze. Nevertheless, I have often found overfeeding or feeding with large pieces of marine flesh to cause the specimen to go through odd shape changes that seemed to affect its longevity. Therefore, if the decision is made to feed, do so sparingly, e.g., twice monthly. Keep in mind if the water movement is too swift, the bubbles will not fully expand, detracting from the natural nourishment provided by the zooxanthellae on the surface of each bubble. And it's also possible a strong current will separate the corals flesh from its skeleton. (WM 1 - 2)

When shopping for a bubble coral, be aware the animal's septa, i.e., the upright large blade-like structures that extend above the corallite walls, are quite sharp and somewhat thin. Therefore handling during collection and/or shipping can easily damage this skeleton material and its associated tissue. It's always better to select a specimen that looks healthy and shows no signs of damage or has any tissue recession, or has any kind of alga growth (brown or green) on any exposed skeleton surface. In fact, if an alga growth is present, chances are slim that the coral will continue to survive since alga encroachment is often unstoppable.

For further information on this coral, checkout an article I wrote titled 'Bubble Coral - Unique and Hardy' for FAMA magazine in 2006, which is posted in part on the 'Articles' page of this website with their approval.


Physogyra

This genus has a Bubble Coral, P. lichtensteini, that is sometimes referred to as the "poor man's bubble coral." This photosynthetic species, which has small bubbles, does much better in an area that receives intense light (PAR 400) and very good water movement (WM 3), and keep in mind, it has 'highly' aggressive very long sweeper tentacles! Not a good species for most reef aquariums!


Family Dendrophylliidae

There's only one reef building genera in this family, and that is Turbinaria. Otherwise, most others in this family are cave dwelling stony corals and difficult to maintain long term without hand feeding once every few days or possibly more often.

Tubastraea

There are seven species in this genus, T. coccinea (East Pacific, Indo-West Pacific, Eastern and Western Atlantic Ocean), T. aurea (Western and Eastern Pacific), T. faulkneri (East Pacific, Indo-West Pacific), T. diaphana (Indo-West Pacific); T. floreana (East Pacific); T. tagusensis (East Pacific); and, T. micranthus. All except for T. micranthus are orange/yellow in color except this species, which has a very dark, somewhat black coloration, and is often called the 'Black Sun Coral' and is found in the Indo-West Pacific.

The most common species, T. coccinea, is frequently available in the trade. It has common names such as Orange Polyp Coral, Rose Coral, and Sun Coral. This non-photosynthetic, non-reef building stony coral does not contain zooxanthellae, and is most often found under overhangs, on deep vertical walls, and/or on cave entrances/walls where the surrounding waters are high in nutrients. Its generally brilliant orange or yellow polyps extend at night to feed upon the higher content of plankton during evening hours.

Aquarists generally find these 'cave' corals in a well-lighted shop tank among other corals that require bright light, and often think because if that's where the shop had it, or because it's a beautifully colored coral, it should be similarly placed in their tank. Such placement in the hobbyist tank would be incorrect, as this species should be placed in a shaded area, where there is fairly good current 'and' where access to it is easy as it must be hand fed, usually daily, to remain healthy. In fact, where this species is concerned, it's probably the most misplaced; incorrectly cared for species in reef tanks that I've ever seen.

When its feeding tentacles are displayed, meaty foods such as fortified brine shrimp, mysis, small pieces of marine fish/shrimp flesh, and/or products containing Cyclop-eeze or similar type products should be placed upon the polyp tentacles. Even though its feeding tentacles are usually only displayed at night, it will sometimes display them during daylight hours if it senses food entering the aquarium. In aquariums containing cleaner shrimp, I would have to place a temporary screen mesh over the opening where the coral was placed to keep the shrimp from pulling tasty morsels out of the polyp until fully engulfed by the polyp!

Be aware there is a small snail, Epitonium billeeanum, commonly called a 'Wentletrap' snail that feeds exclusively upon Tubastrea coccinea. The shell and mantle of this snail is bright orange or yellow, making it difficult to see. There's also a slug, Phestilla melanobrachia, that feeds solely upon Tubastrea. If it feeds on an orange polyp, its orange colored. If it feeds upon a black polyp, it's a black color. Inspect all specimens of Tubastrea carefully and remove these predators. (PAR <100) (WM 2 - 3)

Turbinaria

There are several species of interest in this genus and all are fairly easy to maintain and exhibit little aggression to neighboring corals. The most common form is bowl or goblet-shaped varieties, however, some form scroll or flat plate-like forms and occasionally encrust rocks, columns, or even branches. Environmental factors such as light and water currents are the two conditions that most impact its adapting/forms. Bowl shaped specimens usually come from deeper water where the coral is attempting to gather as much light as possible with its bowl-like shape. Scroll-shaped specimens usually come from shallow water, such as T. reniformis species, which have polyps usually less than 1 mm high. Some may also be quite colorful, such as a yellowish color. When irritated these corals can dispense copious amounts of clear mucus and if it touches other corals, it can damage them as it is presumed to contain nematocysts or a toxin used as a defense mechanism.

Probably the most common and almost always assessable is T. peltata, which hails from the Indo-Pacific Ocean, Australia, Indian Ocean, and Eastern Africa. It is found in protected environments, shallow reef slopes, and foreshores that have turbid water. It's quite hardy and requires moderate light, 3 - 4 watts per gallon (PAR <300), and moderate water movement (WM 2 - 3), and is usually brown, gray or cream in color. Its more erect and always visible polyps can be fed meaty/zooplankton foods to hasten growth. It's a very good beginners coral.

Duncanopsammia

Those in this genus are among the cave dwelling type of stony corals and they are difficult to maintain long term without hand feeding once every few days. The species D. axifuga, hailing from the Western Pacific and Northern Australia, occasionally shows up in the trade. It inhabits fairly deep, 60 feet (20 m) dark sandy areas attached to hard substrates, sometimes at the opening to caves where water current through cave openings tend to bring it sufficient plankton-like foodstuffs. Has a temperature range of 73 to 81°F (23 - 27°C) and requires shaded aquarium areas and at least twice weekly hand feeding with meaty foods and gentle water movement (WM 1). Difficult to maintain long term! (PAR <100)


Dendrophyllia

Those in this genus are non-photosynthetic, non-reef building stony corals and is most often found on deep vertical walls, and/or on cave entrances/walls where surrounding waters are high in nutrients. Its brilliant orange or yellow polyps are generally extended at night to feed upon the higher content of plankton during evening hours.

Usually simply called Dendro's in the trade, but often misidentified as Tubastrea, which is in the same family and looks quite identical! However, Dendro's are far more expensive than Tubastrea specimens since they have only appeared in the trade with any frequency in the last several years and require deep dives into darken areas to collect. And as with any deep-water specimens they must be cared for appropriately or the investment will be lost quickly, as proper placement and hand feeding this coral is a 'MUST' if it is to remain healthy.

As mentioned above, aquarists generally find these 'cave' corals in well-lighted shop tanks among other corals that require bright light and often think because if that's where the shop had it or because it's a beautifully colored coral, it should be similarly placed in their aquarium. Such placement in the hobbyist system would be incorrect, as this species should be placed in a shaded area where there is fairly good current. Nevertheless, where access to it is easy as it must be hand fed every couple of days to remain healthy.

The specimen in the photo cost 250 dollars, had seven polyps and was located on the bottom of my aquarium near the front of an entrance to a cave-like structure. It received no direct light from aquarium lamps, just direct daylight from the front aquarium panel. A long handled stainless steel tweezers was used to feed each polyp small pieces of marine fish or shrimp flesh, or individual defrosted mysis shrimps. Occasionally, very small pellet-sized meaty-based foods were sprinkled onto open polyps to vary its diet. In the beginning, it was necessary to feed daily to keep polyp tentacles extended/visible. Within a month, feeding was reduced to once every two days. If the feeding timeframe was exceeded, e.g., once every three or four days, some polyps remained closed and would not open until hours after the animal's other polyps were fed, sometimes taking several hours for all polyps to open. Over a period of six months I found it best to feed every other day. Within 12 months, the specimen grew 14 more polyps and all tentacles became very sticky, a very healthy sign that the animal was in tip-top shape as shown in the photo!

In aquariums containing cleaner shrimp, it might be necessary to place a temporary screen over the coral while its 'slowing' engulfing its food, as shrimp will steal food bits directly out of an open polyp mouth! This is an annoyance, both to the coral and the aquarist when trying to feed these type corals! In my aquarium, I would offer the shrimp individual pieces of food first, but that did not always prove successful, so a mesh screen placed over the polyps while they are engulfing their foods should be given some thought. That's unless you have the time to keep chasing the shrimp away! If cared for properly, it grows quite quickly and could easily be fragged into smaller segments. Same water movement and PAR as above species.

Note: It was necessary to send a photo of this specimen with its polyps closed, and information as to where it was said to be collected to Dr. Vincent Hargreaves for help in deciphering the species. Even then, the use of 'cf' - an abbreviation of the Latin word "confer" meaning to compare or consult - is being used in the name of this species, thereby suggesting a tentative name/species is being applied/comparing it to an already known correctly described species.

Family Flabellidae

These are ahermatypic solitary cup-like corals, mostly found in caves and around or under rocks, with only one species that I know of available in the aquarium trade.

Rhizo Coral

The species Rhizotrochus typus, commonly called 'Rhizo,' hails from the Indo-Pacific, and inhabits deep protected reef and cave environments. Was mostly collected in southern Japan waters, and was seen in different colors depending upon origin, such as pink, green, yellow, and the more common white color. This non-photosynthetic coral is a solitary (non-colonial) member in this genus and is no longer collected legally, as its been placed on the Endangered Species List.

Nevertheless, probably due to it being easily misidentified for similar looking species when closed, it may occasionally show up in the trade, and when so, needs the same care as do Tubastrea corals, i.e., shaded cave-like areas and individually fed meaty foods at least twice weekly. Has a temperature range of 70 to 81°F (21 - 27°C). Generally a white color, but some nice color variations exist. Does best at the cooler end of the range. Not recommended for beginners.


Family Meandrinidae

There are several genera in this family, yet only one, Meandrina, contains a species of interest to reef hobbyists.

Maze Coral

Meandrina meandrites hails from the Tropical West Atlantic, Gulf of Mexico, and the Caribbean and is commonly called a Brain Coral, Butterprint Brain Coral or Maze Coral. In the wild it's usually found in fairly shallow reef-like environments where it forms massive colonies that appear columnar in shape or free-living forms with meandroid corallites, and most always a light brown or gray color. Does best where water movement is quite brisk (WM 3) and lighting is fairly intense (PAR >300). Seems like a hardy coral, yet rarely seen in the trade, but no doubt a good beginners coral as it seems to be quite hardy.

Lets now move to 'other' forms of invertebrates in the next chapter!