All fish / Acanthuridae

Doctorfish

Acanthurus chirurgus

Also known as doctorfish tang, doctor fish, doctorfish surgeon, barred surgeonfish, atlantic doctorfish, chirurgus tang, doctor tang, ドクターフィッシュ, 外科刺尾鱼, 大西洋刺尾鱼

A grey-brown to bluish surgeonfish with about ten thin dark vertical bars along its sides and a sharp scalpel-like spine on each side of the tail base. It is kept as a hardy, active algae grazer for big reef or fish-only systems, and it mostly leaves corals alone.

Care at a glance

Care level

Moderate

Temperament

Semi

Adult size

30 cm

Temperature

24 to 28 °C

pH

8.1 to 8.4

Smallest tank

800 litres

Keep as

Keep singly, or as a group only in very large systems

Diet

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

Swims

Middle of the tank

Lifespan

10 to 20 years

Water

Marine (saltwater)

Wild range

Western Atlantic from Massachusetts and Bermuda to Brazil, including the Caribbean and Gulf of Mexico; also the eastern Atlantic off West Africa

Breeding

It spawns in groups out in open water, releasing pelagic eggs that hatch into long-lived larvae. It has not been bred in home aquariums in any meaningful way, so almost all fish on sale are wild caught.

Good to know

It grows to around 30 to 39 cm and needs a very long tank with lots of swimming room. The tail spines can cut hands and other fish, and it can be aggressive towards other tangs, especially similar-shaped ones. It is easily confused with the ocean surgeon (Acanthurus tractus/bahianus), which has no body bars.