Masked butterflyfish (Chaetodon semilarvatus) care guide

Group
Marine fish
Other names
Bluecheek butterflyfish, Golden butterflyfish
Family
Chaetodontidae (butterflyfishes)
Origin
North-west Indian Ocean: Red Sea and Gulf of Aden east to Oman; coral-rich areas at 1–20 m.
Water
saltwater
Maximum size
23 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

Care

A large Red Sea butterflyfish; 400 litres is an estimate (adults are often about 15 cm). 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. Usually in pairs or small shoals and often hovers motionless under plate corals for long periods; it is said to be active at night and rest by day. Bright lemon yellow with faint orange vertical lines and a dark blotch behind the eye. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Chaetodonsemilarvatus). Checked October 2026.

Diet

Eats hard corals and bottom-living invertebrates. In captivity offer mysis, chopped shellfish, worms and krill several times a day.

Breeding

An egg-layer that pairs to spawn, usually by day, and is one of few fishes known to keep long-term mates. Not bred in home aquaria.

Compatibility and tank mates

Peaceful; keep singly or as a pair. Not reef safe: it eats hard corals.

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

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