White Spine Surgeonfish (Acanthurus Leucocheilus) saltwater aquarium fish portrait

Acanthurus leucocheilus is a deep-bodied, laterally compressed surgeonfish from the Indo-Pacific. Adults wear dark brown to blackish coloration broken by distinctive pale markings: white-edged lips, a white throat or chest band, a white caudal-peduncle spine, a pale bar near the tail base, and a pale band along the outer pectoral fin. Juveniles look markedly different, appearing brown with a yellow caudal fin. In the wild, this species keeps to clear outer reefs, steep slopes, and water near drop-offs, usually alone or in small groups.

Adult housing should be generous. A 125-gallon aquarium is the practical starting point, though specialist references push considerably higher, with cautious recommendations in the 250- to 300-gallon range for a fully grown fish, so larger is genuinely better here. Prioritize extensive open swimming length paired with sturdy, well-structured rockwork that provides grazing surfaces, shelter, and visual breaks between territories. Turbulent flow, strong oxygenation, robust filtration, and stable water chemistry replicate the energetic outer-reef conditions this fish comes from, and a mature system with established algae growth suits it best.

This is a grazing herbivore that works over sand and reef surfaces in nature, taking algae and detritus throughout the day. In the aquarium, marine algae should form the foundation of the diet. Dried nori, fresh macroalgae, Spirulina, and vegetable-based flakes or pellets all serve well, and access to filamentous algae and microalgae on rockwork lets the fish browse the way it would on a reef.

Meaty marine foods may be offered occasionally for variety, but plant nutrition needs to stay dominant. Feed two or three times daily, or offer nori on most days supplemented by one or two smaller feedings. Keeping this fish consistently well fed matters beyond nutrition alone, since an underfed specimen becomes far more likely to sample invertebrates and coral tissue.

Dried Nori Fresh Macroalgae Spirulina Herbivore Flakes Vegetable-Based Pellets Rockwork Microalgae
Expect a powerful, near-constant swimmer that patrols open water and returns repeatedly to favored grazing spots. Although it is not an aggressive fish by nature, it will establish and defend territory, and it reacts most strongly to other surgeonfishes and similarly shaped tangs. Cramped quarters sharpen that response considerably. Plan on one specimen per system unless the aquarium is exceptionally large.

Choose tankmates that are calm but substantial enough to hold their own at the food dish, and skip fin-nippers along with very timid fishes that would be crowded out. In a reef display, this species is generally compatible with corals and can be kept among them, but mobile and sessile invertebrates deserve monitoring, especially if feedings lapse. Frequent algae-based meals are the most reliable way to keep grazing attention on rockwork rather than ornamental invertebrates.

FAQ

Frequently Asked Questions

About the White Spine Surgeonfish

  • How large does the White Spine Surgeonfish get?
    It reaches roughly 10 inches in the aquarium, while scientific records for wild fish report maximums near 18 to 19 inches. Plan housing around a large, actively swimming adult.
  • How often should this surgeonfish be fed?
    Two or three feedings per day suit its constant grazing habit, or offer nori on most days plus one or two smaller feedings. Consistent algae availability keeps it in good condition.
  • Can it share a tank with other tangs?
    It tends to challenge other surgeonfishes and similarly shaped tangs, so one specimen per system is preferred unless the aquarium is exceptionally large.