Blue lined surgeonfish (Acanthurus nigroris) care guide

Group
Marine fish
Family
Acanthuridae (surgeonfishes and tangs)
Water
saltwater
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
450 litres
Care level
intermediate
Temperament
semi_aggressive
Reef safe
yes

Care

Tank and decor: an active, open-water swimmer that needs a long tank with plenty of swimming room, live rock for grazing and strong, well-oxygenated flow. Minimum tank: about 450 litres (an estimate based on the typical size of related tangs, as the list gives no maximum size and active swimming). Water: our sources give no species-specific figures, so the values here are general marine aquarium guidance, not species-specific: 24–27 °C, pH 8.1–8.4 and specific gravity 1.023–1.026. Keep nitrate low and the water well oxygenated. Behaviour and identification: a brownish surgeonfish with fine blue lines along the body. The list gives no maximum size. Safety: like all surgeonfishes it has a sharp, scalpel-like spine on each side of the tail base that can cut hands and get caught in nets. Use a container to move it. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies). Checked October 2026.

Diet

Herbivore. Offer marine algae every day: dried nori or seaweed sheets on a clip, spirulina- and seaweed-based flakes and pellets, and frozen herbivore foods, with occasional mysis. Live rock with algae growth helps. Several feeds a day suit it best.

Breeding

Our sources for this page do not describe breeding. Tangs spawn in open water and have long-lived planktonic larvae, and almost all aquarium tangs are wild-caught.

Compatibility and tank mates

Reef safe: it leaves corals and invertebrates alone, though it grazes algae. It can be territorial towards other tangs, especially similar-looking ones, so add tangs at the same time in a large tank, or keep one per tank.

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

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