Achilles Tang

Achilles Tang (Acanthurus achilles): One of the most iconic and challenging surgeonfish in the hobby Deep black body with a bright orange teardrop marking near the caudal peduncle and a white‑rimmed tail Highly active, powerful swimmer that reaches 8–10 inches Best suited for large, mature reef systems with excellent water quality and strong flow Origin & Habitat Native to the Central and Eastern Pacific, especially Hawaii, Tahiti, and the Marquesas Found on high‑energy reef slopes with strong surge and oxygen‑rich water Constant grazer on filamentous algae and biofilm Temperament & Reef Safety Semi‑aggressive, especially toward other tangs Territorial in smaller tanks Reef‑safe — does not harm corals or invertebrates Needs ample swimming room to reduce stress and aggression Tank Requirements Minimum 180–220 gallons (larger strongly preferred) High flow and strong oxygenation Large open swimming lanes plus rockwork for grazing Water parameters: 75–80°F, pH 8.1–8.4, salinity 1.023–1.026 Extremely sensitive to poor water quality, low oxygen, and parasites Tight lid recommended — fast swimmer that can bolt when startled Diet Primarily herbivore Constant grazer on filamentous algae In captivity, feed: Nori sheets Spirulina pellets Algae‑based flakes Seaweed blends Occasional mysis or plankton for variety Multiple small feedings daily help reduce aggression and maintain weight Compatibility Works well with peaceful reef fish Use caution with: Other Acanthurus tangs Large aggressive angels Similar‑shaped surgeonfish Best kept solo unless the tank is extremely large Safe with corals and most invertebrates Why Hobbyists Love It One of the most visually striking tangs in the hobby Graceful, powerful swimmer with constant motion Iconic coloration and presence in large reef displays Considered a “showpiece” fish for advanced aquarists