Raccoon butterflyfish (Chaetodon lunula) care guide

Group
Marine fish
Other names
Crescent-masked butterflyfish, Lunule butterflyfish, Halfmoon butterflyfish, Moon butterflyfish, Raccoon coralfish, Redstriped butterflyfish
Family
Chaetodontidae (butterflyfishes)
Origin
Tropical Indo-Pacific from East Africa to Hawaii and the Marquesas, north to southern Japan, and South Africa; seaward reefs and lagoon reef flats.
Water
saltwater
Maximum size
20 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
400 litres
Care level
intermediate
Temperament
peaceful
Reef safe
no
Lifespan
5–7 (captivity) years

Care

A hardy butterflyfish for a large, mature tank; 400 litres is an estimate from its size. Water figures given here are general marine aquarium guidance, not species-specific: 24–27 °C, pH 8.1–8.4 and a specific gravity of 1.023–1.026. Keep nitrate low and water quality stable. Mostly active at night and usually found in small groups in the wild. It is prone to marine white spot (Cryptocaryon) in confined tanks, so quarantine it carefully. Yellow with a dark saddle and a black-and-white mask. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Chaetodonlunula). Checked October 2026.

Diet

Eats mainly nudibranchs and other small invertebrates, plus algae and coral polyps. In captivity it accepts mysis, chopped shellfish, krill and algae-based foods.

Breeding

Not described in the sources. Not bred in home aquaria.

Compatibility and tank mates

Generally peaceful, though it may squabble with lionfish and triggerfish. Not reef safe: it eats soft corals and may damage other invertebrates. It is useful in fish-only tanks for clearing pest anemones such as Aiptasia and Majano, usually within two to six weeks.

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

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