Black-tailed Butterflyfish can be found in shallow lagoons and the outer slopes of coral reefs, from the surface to 30 m below.
It lives on its own or as a couple. It tends to be relatively sedentary and occupies a vast territory that it defends against other butterflyfish. The juveniles prefer branched corals in the shallows and will stay close to the same colony until they reach maturity.
This species feeds almost exclusively on hard coral polyps (the living part of the coral) and sometimes on anemone tentacles and gastropod eggs.