Sailfin tang

The sailfin tang is a large surgeonfish of the family Acanthuridae, native to the Indo-Pacific. It is disc-shaped with tall dorsal and anal fins that give it a sail-like profile, patterned with alternating dark and pale vertical bands and fine markings; it can raise its fins to appear even larger. It is a robust, semi-aggressive herbivore that grazes constantly on algae. It can be territorial toward other tangs, particularly of similar shape, so it is usually kept singly unless the tank is very large. It is generally reef-safe and coexists with most non-tang tankmates. Due to its adult size and need to swim, it requires a large aquarium with plenty of live rock for grazing and hiding. Its diet must be predominantly vegetable-based, including dried marine algae (nori), algae-based preparations, and some meaty supplements. Good water quality and vitamin-rich feeding help prevent lateral line disease common in tangs.