Copperband Butterflyfish (Chelmon rostratus)
Copperband Butterflyfish (Chelmon rostratus) known to tropical fish keeping enthusiasts as the Beaked Butterflyfish, Beaked Coralfish, or Orange Stripe Butterfly are found in the Western Pacific from Andaman Sea to the Ryukyu Islands, and Australia.
Copperband Butterflyfish are usually encountered as single fish or in pairs in estuaries, silty inner reefs, and rocky shorelines of the coral reefs of their range, at depths to 85 feet where they are often seen feeding on plankton, worms, sea anemones, shrimp, clams, and sponges.
Although Copperband Butterflyfish are solitary, shy, and peaceful; they will aggressively defend their territories against any perceived threat. Unmated Copperband Butterflyfish have no problem living solitary lives on the reef.
Copperband Butterflyfish (Chelmon rostratus)
Copperband Butterflyfish have a pearlescent silvery white body color with black edged, orange gold vertical bands, a false black eyespot on the upper rear of the dorsal fin, a white edged black vertical band on the caudal peduncle, and a long, narrow, nose and mouth. The light yellow orange and white pectoral fins have a tinge of yellow, with a translucent caudal fin. Males and females cannot be visually distinguished by size or color.
Copperband Butterflyfish are best housed in a mature reef or FOWLR aquarium of at least 125 gallon capacity with a deep Oolitic Aragonite or coralline sand substrate, plenty of aged live rock arranged into crevices, caves, and overhangs for them to graze on and hide among, and plenty of free swimming space.
Chelmon rostratus are unbelievably sensitive to changes in water quality. Fluctuations in specific gravity, pH, water hardness, and temperature will very quickly adversely affect the health of the fish. An efficient filtration system, protein skimmer, and power head or wave maker to provide a moderate, steady current and oxygenate the water is required to keep the fish healthy. Changing about 10% of the tank volume water every two weeks is also recommended for this species.
Although Copperband Butterflyfish are considered reef safe and will generally not eat corals; some tropical fish keeping enthusiasts have reported them nipping at small polyp stony corals (SPS) and occasionally picking on coral polyps. They will search for food in between the coral polyps with their long snouts which could potentially damage delicate corals.
Chelmon rostratus are fond of picking on invertebrates, especially anemones and feather dusters. They relish eating Aiptasia, or glass anemones, and are often specifically introduced into reef tanks to control them. Any decorative shrimps, clams, mollusks, or small invertebrates you may have in your reef tank could also be targeted.
Copperband Butterflyfish thrive in very large reef tanks and in peaceful FOWLR community tanks provided they are not kept with conspecifics or similar butterflyfish. They do not mix well with others of the same species.
Friendly, small to medium sized species that do not compete with Copperband Butterflyfish for food make good tankmates.
The following species make excellent tankmates for your Copperband Butterflyfish:
Blue Green and like type Chromis
Cardinals (Pajama Cardinal)
Clownfish
Damselfish
Dartfish (Fire Dartfish)
Dottybacks
Dragonets (Mandarin Goby)
Dwarf Angelfish like (Bicolor Angel)
Gobies
Including larger, more predatory species with Copperband Butterflyfish should be avoided, or closely monitored. When they become stressed, cold, or sick they become either aggressive or listless and may stop eating.
Copperband Butterflyfish are extremely difficult to breed in an aquarium environment for a number of reasons.
Because males and females are virtually impossible to sex; establishing a mated pair is rarely accomplished. Copperband Butterflyfish can fight to the death when housed with conspecifics and when attempting to select a pair; the fish can hurt or kill each other if they are not constantly monitored. Should you luck out and establish a breeding pair, it is extremely rare for them to successfully lay and hatch out their eggs. Additionally, feeding the young fry and juveniles is extremely difficult. Most, if not all fry will starve to death.
In their natural environment on the reefs, Copperband Butterflyfish are monogamous and form up into pairs during breeding. After a sort mating ritual, the female will deposit her eggs on a rocky surface and the male will shimmy over them to fertilize them. Both parents aggressively defend their brood from predators. The tiny hatched out fry have a unique plating that protect them from predators.
In their natural habitat, Copperband Butterflyfish eat plankton, worms, sea anemones, shrimp, and sponges.
When initially introduced into an aquarium environment, they often will either not eat or be picky eaters that must be enticed to eat.
Live brine shrimp, blackworms, frozen Mysis shrimp or worms tucked into a piece of live rock, or a crushed live clam in its shell will often get the fish eating. Invasive populations of Aiptasia in your tank can often get the fish feeding.
Once the fish is eating, they should be fed a high protein flake food or pellet supplement along with live or frozen meaty foods like Mysis shrimp, brine shrimp, clams, bloodworms, and chopped seafoods. Small portions should be fed several times a day, but refrain from overfeeding as it can stress out their digestive system. Experiment with different types of food until you find what the fish will readily accept.
Copperband Butterflyfish (Chelmon rostratus) are readily available to tropical fish keeping enthusiasts from a variety of online suppliers and specialty fish shops at prices that vary according to size and area of collection.
Approximate purchase sizes: Small: 1″ to 2-1/2″; Medium: 2-1/2″ to 4-1/4″; Large: 4-1/4″ to 5″; Extra Large: 5″ to 6-1/2″
Currently prices for small specimens start at around $69.99 for small Indonesian specimens, up to $499.99 for large specimens.
Copperband Butterflyfish (Chelmon rostratus)
Minimum Tank Size: 125 gallons
Aquarium Type: FOLR or Reef
Care Level: Difficult
Temperament: Peaceful
Aquarium Hardiness: Moderately Hardy
Water Conditions: 75°F to 79°F, dKH 8 – 12°, pH 8.1 – 8.4, sg 1.020-1.025
Max size: 8″
Color Form: White, Black, Orange, Yellow
Diet: Carnivore
Compatibility: Reef with Caution
Origin: Indo Pacific
Family: Chaetodontidae
Lifespan: 5 – 8 years
Aquarist Experience Level: Intermediate
