Copperband butterflyfish (Chelmon rostratus) care guide

Group
Marine fish
Other names
Beaked coralfish, Copperband
Family
Chaetodontidae (butterflyfishes)
Origin
Indian and Pacific Oceans; coral reefs, rocky shores, estuaries and silty inner reefs at 1–25 m.
Water
saltwater
Maximum size
20 cm
Temperature
24–29°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
300 litres
Care level
expert
Temperament
peaceful
Reef safe
with_caution

Care

Wikipedia suggests a tank of at least 75 US gallons (about 285 litres; 300 given here) with plenty of live rock, and 24–29 °C. Other figures (pH 8.1–8.4, SG 1.023–1.026) are general reef aquarium guidance. It is not recommended for inexperienced keepers. It is territorial towards its own kind and lives singly or in pairs. Aquarium fish are usually about half the wild size. Silver with gold bars edged in black, a long snout and a black eyespot on the dorsal fin. Choose a fish that is already eating well before you buy, and introduce it to a mature, settled tank. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Chelmonrostratus). Checked October 2026.

Diet

Picks small invertebrates from rock with its long snout, including tubeworms, small anemones such as Aiptasia (not its favourite), and other worms, clams and molluscs. Captive fish often need live or fresh foods (mysis, chopped clam, worms) to start feeding and should be fed several times a day.

Breeding

An egg-scatterer that forms monogamous pairs. Not bred in home aquaria.

Compatibility and tank mates

Peaceful with other fish but keep one per tank unless you have a known pair. Wikipedia calls it reef safe, but the list rates it "with caution": it can eat tubeworms, clams and other desirable invertebrates. Avoid boisterous tankmates that outcompete it at feeding time.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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