Acanthurus tristis

Acanthurus tristis, commonly known as the Indian Ocean mimic surgeonfish, is a medium-sized tang. It mimics the colors and pattern of Centropyge eibli when juvenile. When older it turns beige-brown with a greyish head. It can be aggressive towards other tangs and food competitors, but will generally leave other fish a lone. A great algae eater for a tank with enough swimming space.

Like other tangs, it will eat meaty foods, but it's important it can graze on algae/seaweed the entire day to ensure it will stay healthy. So feed flakes/pellets multiple times a day and make sure there is always seaweed available.