Convict Surgeonfish

About

The convict surgeonfish (Acanthurus triostegus) is named for the five bold vertical black bars running down its pale greenish-yellow body. A pattern that makes it one of the easier tangs to identify at a glance. It ranges widely across the Indo-Pacific and into the eastern Pacific, from the lower Gulf of California down to Panama, turning up on lagoon reefs, seaward reef faces, and even in tide pools where juveniles are especially common. Adults gravitate toward hard substrate areas, and you will often find them grazing near freshwater runoff zones where algae-covered rocks provide a productive feeding patch. In the wild, convicts sometimes gather in sizable groups to feed on filamentous algae, and they form spawning aggregations. A behavior dramatic enough to attract hungry eagle rays looking to capitalize on the clouds of eggs and sperm released. In the aquarium this is one of the more relaxed surgeonfish, with notably small scalpels at the tail base and a generally non-confrontational attitude toward tankmates. The usual tang caution still applies when housing it alongside similar-looking or closely related species. It is a constant swimmer that needs room to move, and its herbivore diet should be well supported with regular offerings of algae-based foods.