Doctorfish (Acanthurus chirurgus) care guide

Group
Marine fish
Other names
Doctorfish tang, Surgeonfish
Family
Acanthuridae (surgeonfishes, tangs and unicornfishes)
Origin
Western Atlantic, Massachusetts to Brazil and possibly tropical West Africa; rocky outcrops and coral reefs. Rare records from the central Mediterranean.
Water
saltwater
Maximum size
39 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
1000 litres
Care level
intermediate
Temperament
semi_aggressive
Reef safe
yes

Care

Tank: a large, long tank with live rock to graze and open swimming room. an estimated minimum of about 1000 litres (our estimate from the adult size and habits). Water: our sources give no species-specific figures, so the values shown (24–27 °C, pH 8.1–8.4, SG 1.023–1.026) are general marine aquarium guidance, not species-specific. Like other surgeonfish it needs well-oxygenated water with strong flow and stable quality. Behaviour: an active daytime grazer. It uses its tail blades in fights with others of its kind and against predators, so keep one per tank unless the system is very large. Tangs are prone to marine white spot (Cryptocaryon irritans) and velvet, so quarantine new arrivals. Handling: like all surgeonfish it carries a sharp, scalpel-like blade on each side of the tail base that it raises when threatened and that can cut hands deeply. Move it in a container rather than by hand. Identification: the article gives up to 39 cm and 5.1 kg. Trade and status: assessed by the IUCN (2012). Not CITES-listed. Selling: our policies require the adult size and long-term tank needs to be stated clearly in the listing. Large fish must travel by a specialist live-animal courier (see the Livestock shipping guide). Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Acanthuruschirurgus). Checked October 2026.

Diet

A daytime grazer of algae and organic detritus, which it scrapes off rock and grinds in a thick-walled, gizzard-like stomach. Offer plenty of marine algae (nori, macroalgae), spirulina-based foods and some meaty foods, several times a day.

Breeding

Spawns in groups in the evening. Eggs are under 1 mm and float on an oil droplet; larvae hatch within 24 hours, settle at about 25 mm and mature in roughly nine months. Not bred in home aquaria.

Compatibility and tank mates

Reef safe with corals and invertebrates. Aggressive towards other doctorfish and may squabble with other surgeonfish; mixes with most non-tang community fish.

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

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