Tennent tang (Acanthurus tennenti) care guide

Group
Marine fish
Other names
Lieutenant tang, Tennent's surgeonfish
Family
Acanthuridae (surgeonfishes, tangs and unicornfishes)
Origin
Indo-Pacific, East Africa and Madagascar to Sri Lanka, Malaysia, Thailand and Indonesia; rocky and coral reefs, slopes and channels at 1–40 m.
Water
saltwater
Maximum size
50 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 tank with open swimming space and sand and rock. 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. The article gives 25–29 °C in the wild. Behaviour: feeds in the open by day, often in small groups with parrotfish. Typical adults are 25–31 cm; the article gives up to 50 cm. 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. Trade and status: commonly traded. IUCN: Least Concern; vulnerable to reef destruction but found in several marine protected areas. 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/Acanthurustennenti). Checked October 2026.

Diet

Eats bottom algae, detritus and the algal film on sand and other surfaces. Give marine algae, nori and spirulina-based foods several times a day, with some meaty foods.

Breeding

Fertilisation is external: females release eggs near the reef and males follow and release sperm. Larvae drift for about seven weeks before settling. Breeding runs July–August, and males colour up in the season. Not bred in home aquaria.

Compatibility and tank mates

Reef safe. May fight with other Acanthurus tangs.

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

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