Bluecheek Butterflyfish

Geographic Origin and Biotope: Endemic to the Red Sea and Gulf of Aden. Found associated with coral-rich reefs, often sheltering under large table corals (Acropora) at depths of 3 to 20 meters.

Taxonomy and Morphology: Iconic member of the genus Chaetodon. Features a deep, circular, highly compressed body. Grows to a relatively large size of 23 cm (9 inches).

Social Behavior: Peaceful and monogamous. In the wild, they are almost always observed in mated pairs or small, tight-knit groups that stay close to coral overhangs.

Coloration and Sexual Dimorphism: Body is a brilliant solid saffron-yellow, marked with fine vertical orange stripes and a prominent bluish-grey patch behind the eyes (resembling a mask). No visible sexual dimorphism.

Aquarium Setup: Requires a very large aquarium of at least 500 liters with plenty of open swimming area and sturdy rocky structures that replicate reef caves and overhangs.

Diet and Feeding: Carnivorous/Corallivore. Naturally feeds on coral polyps. In captivity, it must be acclimated to meaty frozen foods (mysis, brine shrimp, chopped clams/mussels served on the half shell). Feed 3 times daily.

Water Quality: Highly demanding. Needs pristine water quality, efficient protein skimming, and zero ammonia/nitrites: temperature 24-27°C (75-81°F), pH 8.1-8.4, specific gravity 1.022-1.025, GH 15-25, and KH 8-12.

Compatibility and Tankmates: NOT reef-safe with stony corals (SPS/LPS), which it will devour. Best kept in a FOWLR setup or with select tough soft corals. Ideally housed as a mated pair.

Aquarium Reproduction: Unrecorded in home systems. Pelagic spawners.

Risks and Diseases: Delicate during the initial feeding acclimation phase. Highly susceptible to marine ich and sensitive to pH fluctuations.