Saltcorner
By Bob Goemans
Site Supported in Part by:
RedSea 

Bob Goemans corresponds with Jerry Sparrow (Noblesville, Indiana)

Jerry Sparrow (Noblesville, Indiana) writes...

Dear Mr. Goemans

In 1979 I was fortunate enough to be stationed in Key West Florida while I was in the US Navy. At that time I became interested in the marine aquarium hobby. Now needless to say since I was in the keys I did not use synthetic sea salts. A few quick trips to the beach and I had my aquarium up and running. At that time undergravel filters were all we had. I improvised a system at that time using a power filter to hold a large amount of dolomite and a block of filter material. I termed this setup a bacteria pump and it worked quite well. Man what a difference today! With protein skimmers, UV sterilizers, plenums, live sand, etc. Well guess what, I am as lost today as if I were just starting those twenty some years ago. My questions are these.

1. I'm thinking of setting up a plenum in a sump using the Jaubert system with 1/2 live aragonite and 1/2 plain aragonite, and also a plenum in my 46 gallon show tank. I wonder if I use 1/2 live aragonite and 1/2 plain crushed coral in either plenum and possibly add 1 gallon of natural/live seawater to both systems, would that cut down on the amount of time the sand beds need to activate? Would there be any real biological benefit to this setup? And, should all of the live material be mixed with the "dead" sand to allow the tank to cycle quicker?

2. With all of this biological filtration will any mechanical filtration be necessary other than the skimmer?

3. I am quite ignorant about the many species of coral. What corals would be best suited to this type of setup with 160 watts of fluorescent lighting incorporating 6500K 40 Watt tubes?

4. What do the blue actinic tubes do for the tank and are they really necessary?

5. I have heard you say one needs to be patient when setting up this type of system. What specifically are the points one needs to be patient about?

Thank you so much for this awesome service and thanks for answering my many questions!

Jerry Sparrow - Noblesville, Indiana

Bob replies...

Hi Jerry,

Its 'Bob" and thanks for your letter. Yes indeed, things have radically changed during the past two decades! And I think your last question about "patience" is probably the most important. If you don't have it while setting up your system, then usually something sooner or later develops and causes either a lot of wasted time to correct, or a lot of wasted money. Sometimes both! And with the tools available these days, beginning any size aquarium is quite easy 'if' you understand what these tools accomplish, how and why they accomplish it, how to use them, and which ones you really need to accomplish your goals.

As for goals/patience, some hobbyists may want a fish only system containing a mix of compatible tankmates. Or maybe a system designed for digging or burrowing type fish. Maybe a nutrient rich system for growing various types of algae. Could be a nutrient poor system for stony corals or a mixed reef system containing both soft and stony corals. Once 'direction/goals' is resolved, which includes the knowledge needed to adequately support the desired animals, its time to look at what's needed in the way of equipment to support that goal and what the budget will allow as to the size of the project. Once that's all out of the way and the aquarium and equipment is purchased, the systems biological processes need to be started. And whatever the direction, those biological/bacteria processes need to be implemented before animals of any significant size or quantity can be placed in the system. Keep in mind their waste products must be adequately processed, which the bacteria in certain areas of the system will accomplish. The thing to do is then get them, the bacteria, adequately established, and that takes some more patience! Its not an overnight process, and in fact, can take a month or more. Keep in mind, if the system were too quickly loaded with animal life, the fish would die in their own toxic sea of waste and some invertebrates would also be harmed or lost.

So much "PATIENCE" is not only needed in getting to the point of adding water to the empty aquarium, its also necessary for establishing the necessary biological processes. And whether those bacteria processes are established in a sandbed, trickle filter or fluidbed filter, its still going to take at least a few weeks to get them to the point where the various classes of bacteria throughout the aquarium are coordinated with each other and are delivering a useful/effective/safe end product. That is to say ammonia is quickly and safely transformed to nitrate. Then once the nitrification cycle is effective, bioload, especially that of fish as they produce the most waste, can then be ramped up slowly. Of course, how many are added and how often depends upon their size and feeding requirements. And if you want to understand just what classes of bacteria are involved, what they accomplish, and what areas in your aquarium they occupy, then recommend reading some of my booklets, especially my 'Natural Aquariums" booklet. You can view the Table of Contents of all my various books by visiting my website at saltcorner.com. In fact, there's a lot more information on my site that will help you in achieving your goals.

As for question 3, your goal appears to be a reef environment, one that will have to be limited to somewhat low light corals since your lighting is not adequate for those requiring more intense light. And if we move from there, then corals such as mushroom corals, brain coral (Trachyphyllia geoffroyi), bubble coral (Plerogyra sinuosa), Anchor Coral (Euphyllia ancora), Frogspawn Coral (Euphyllia divisa), Fox Coral (Nemenzophyllia turbida), Blastomussa merleti or wellsi, are among the good choices as they can do well on about 3 watts per gallon. And there are also a variety of feather dusters and shrimp that can be added and will also do well in this type environment. If you want more light loving corals, you'll have to double the presently available light. And if you do that, then other possible areas such as the heat generated will have to be addressed.

When it comes to Question 1, there are several answers. If a plenum were to be used in the sump, then this enclosure should mainly be used only for filtration purposes, not to house other equipment that require excessive water movement or block its sandbed surface area and/or interfere with its maintenance. And if this sump plenum idea is still feasible, it should 'at least' have a surface area of about one quarter of the surface area of the main tank. If so, then only a shallow sandbed is needed in the main tank, i.e., about one inch of sand about 2 - 5 mm in grain size. This is of course the same grain size as used for the plenum. And if the sump plenum continues to be feasible, than another plenum in the main tank is unneeded duplication, besides additional maintenance.

Even though I like and really prefer the plenum to be in an interconnected tank/sump (for efficiency and maintenance purposes, it really depends on whether or not that sump 'has' to be used to house some major equipment, e.g., a major size system water return pump or large protein skimmer. If that's the case, then maybe a another dedicated sump or tank for the plenum is needed if the user does not want it in the main tank. And as for the half-and-half thought, many go that way to save on the cost of all live sand. However, with so many quick bacteria starting additives on the market, the need for live sand has become greatly reduced, if not eliminated. Actually, the difference between using an additive on all dead sand and that of half-and-half may only be a few days of time in the initial culturing/nitrification process. And as for the use of a fairly expensive aragonite substrate, I used crushed coral in several plenum systems, and it has worked quite well over the long term. Yet these were fairly simply systems without many calcium demanding corals. And since your system may go this direction, i.e., less calcium demand, because of your limiting light factor, you might want to consider using only a quality brand crushed coral. In fact, it can be ordered with live bacteria. Hopefully this answer's your first question.

Thank goodness you have already decided to use a protein skimmer! It is in my opinion the most useful tool we aquarists have! Helps keep nutrients low and provides more dissolved oxygen in the bulk water. Anyway, yes, some simple form of mechanical filtration is needed, if only to keep course matter from clogging small water pumps. Yet, its not necessary for all the water to flow through this form of filtration, as I use it solely to capture floating flying insects attracted by the aquarium's lights.

As for 'blue' actinic lamps, that wavelength of light (420 nm) helps make the environment look more natural. Keep in mind that when it comes to the visible light spectrum, blue light is seen to penetrate the deepest. And in the coral reef environment in the wild, after about 15 to 20 feet mostly this blue light lights it as other wavelengths are filtered out. And since corals below about 15 feet utilize this blue light for photosynthesis, it is important for their wellbeing, besides simply presenting a more nicely looking environment in the aquarium to the human eye. And separate actinic-only lamps are useful in providing a sunrise and sunset photoperiod for all the animals in the aquarium. By having one or two of these type lamps coming on about 30 minutes before the main system lights come on and staying on about the same time length after the main lights go out, the animals are not overly stressed. And as for 6500 Kelvin lamps, I find them giving off a very yellowish light and if not incorporated with separate actinic lamps, the aquarium environment does not appear very natural looking to the human eye. Yet, the light itself, i.e., their available spectrum, is sufficient for the corals that need light. I prefer and use 10K lamps.

Hopefully, this answers your questions and keep me posted.

Bob

Keywords:

Plenum; Aquarium Setup Advice; Actinic Lighting

Other Advice Letters

Site Supported in Part by:
Ocean Nutrition