Found in small schools in very shallow water close to the bottom. Prefer hard bottoms of compacted sand with rock or coral debris. Solitary adults and groups of 3 or 4 adults have also been observed. Feed on a wide range of benthic algae. May suddenly stop and erect its fins (dorsal, anal and pelvic) presenting an encircling array of spined to potential predators; these spines are venomous. A food fish that is occasionally poisonous (Ref. 4537). Probably does not adapt well in captivity (Ref. 12382). Minimum depth from Ref. 9710.