All fish / Acanthuridae

Convict Tang

Acanthurus triostegus

Also known as convict surgeonfish, convict surgeon, manini, five-banded surgeonfish, zebra surgeonfish, convict tang, シマハギ, 横带刺尾鱼, 五带刺尾鱼

A pale greenish white surgeonfish crossed by six narrow black bars, which gives it a striped, convict-like look. It is kept for its smart pattern, active swimming and its habit of grazing nuisance algae in reef tanks.

Care at a glance

Care level

Moderate

Temperament

Semi

Adult size

17 cm

Temperature

24 to 28 °C

pH

8.1 to 8.4

Smallest tank

500 litres

Keep as

Singly, or as a large group in a very big tank

Diet

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

Swims

Middle of the tank

Lifespan

5 to 10 years

Water

Marine (saltwater)

Wild range

Indo-Pacific and eastern Pacific, from East Africa to Hawaii and the Gulf of California

Breeding

In the wild it spawns in large groups, releasing eggs into open water, and the larvae spend a long time drifting as plankton. It has not been bred in home aquariums.

Good to know

It needs plenty of swimming room and a steady supply of algae, and can quarrel with other tangs; like all surgeonfish it carries a sharp blade near the tail, so handle it with care. It is also prone to marine white spot.