All fish / Acanthuridae

Indian Ocean Mimic Surgeonfish

Acanthurus tristis

Also known as mimic surgeonfish, indian mimic tang, indian ocean mimic tang, mimic tang, shadow surgeonfish, yes, 忧郁刺尾鱼

Juveniles copy the look of the Eibl's dwarf angelfish, with an orange-yellow body and dark tail, while adults turn dark brown to grey with a pale spot behind the eye and an orange patch around the tail spine. It is kept as an active algae grazer that adds movement to large reef and fish-only tanks.

Care at a glance

Care level

Moderate

Temperament

Semi

Adult size

22 cm

Temperature

24 to 28 °C

pH

8.1 to 8.4

Smallest tank

700 litres

Keep as

Singly, or one per tank unless the aquarium is very large

Diet

Herbivore: nori and other marine algae, spirulina-based flakes and pellets, plus some mysis and brine shrimp

Swims

Middle of the tank

Lifespan

10 to 15 years

Water

Marine (saltwater)

Wild range

Indian Ocean: Maldives, Sri Lanka, India east to Bali and western Australia

Breeding

It spawns in pairs or groups in open water and releases pelagic eggs. It has not been bred in home aquariums, so all fish in the trade are wild caught.

Good to know

Needs a long tank with plenty of swimming room and will fight with other surgeonfish, especially similar-shaped ones. The scalpel-like spine at the tail base can cut hands and tankmates, and it is often confused with the Pacific mimic, Acanthurus pyroferus.