Saltcorner
By Bob Goemans
Site Supported in Part by:
Real Reef Rock 

Chelmon

Chelmon muelleri

(Klunzinger, 1880)

Muelleri Butterflyfish, Blackfin Coralfish

Likely Reef Tank Suitable

Likely Fish-Only Tank Suitable

Range: Indo-Pacific Ocean: Endigenous to Northwestern Australia.

Size: 7 inches (18 cm)

Natural Environment: Inhabits shallow coastal muddy and algae covered areas in lagoons and estuaries and is often found in turbid sheltered areas. Generally occurs at depths of 3 – 30 feet (1 – 10 m) and mainly feeds on worms, clams, tunicates, and crustaceans. Adults occur singly or in pairs, while juveniles are solitary.

General Husbandry: Not as colorful as others in this genus, yet still attractive having a silvery-white body with several wide tannish orange vertical bands, a long narrow snout used to search crevices for food, and a black false eyespot on the rear upper body and lower dorsal fin. In fact, it grows a bump on its forehead that is thought to be used in head-to-head fighting with others in its genus.

Usually adapts quite easily in larger reef style aquariums or peaceful fish-only community aquariums. A meaty diet of live fortified brine shrimp, black worms (Lumbriculus variegatus), red worms (genus Tubifex) and/or mysis are usually eagerly accepted and should be offered several times daily.

Even though it can be maintained in reef aquariums with most soft and stony corals, its not fully trustworthy as its been known to nip at feathern dusters, and occasionally clam mantles. It’s also often purchased because it will decimate Aiptasia anemones, yet that does not always prove to be correct all the time, especially if more suitable/preferred foods are available. It will also consume small decorative tubeworms and other useful small worms.

Sometimes difficult to get feeding in an aquarium, therefore, supplying it live foods such as feeder shrimp and bloodworms can aid in helping it get used to life in the aquarium. Also, small human consumption clams/black mussels purchased in local grocery stores and placed on the half-shell in the aquarium will entice them to begin feeding. Over time, frozen foods like mysis and brine shrimp will be more readily accepted.

Taxonomy:

    Order: Perciformes

    Suborder: Percoidei

    Family: Chaetodontidae

    Genus: Chelmon

FYI: Preferably maintained without others in the same genus, except as a male-female pair, as it can become quite territorial and battle others for territorial rights.

Pressing some soft foods into openings/crevices on a piece of old dead coral skeleton can sometimes encourage finicky eaters to begin feeding. Nevertheless, probably the best species in this genus, and once settled in is quite hardy. Will even accept flake food.

Experience Level: Intermediate

Temperament: Peaceful

Diet: Carnivore

Coral Safe: Caution advised

Invertebrate Safe: Caution advised

Acclimation Time: 30 minutes+

Aquarium Environment: Reef aquarium (see above) and fish-only aquarium.

Tankmates: Peaceful or non-aggressive

Minimum Tank Size: 100 gallons

Temperature Range: 70 - 82°F (21 – 27°C).

Specific Gravity: 1.020-1.026

pH: 8.0 - 8.5

 Chelmon muelleri (Muelleri Butterflyfish, Blackfin Coralfish)
Photo © John Randall
Site Supported in Part by:
Hikari