Butterfly fish can be highly territorial and require lots of space in which to establish their territory. Though some species may be comfortable swimming in schools, the majority prefer to pick a mate and swim in pairs; this is a species that will mate for life.
Though some breeds of Butterfly fish will eat anything you give them, this species thrives best with a live coral polyp to live off of, a little vegetation, and some fresh meat. It is important to learn what sort of diet the particular species you are considering requires as some have more stringent dietary requirements than others, but most will be fine with shrimp, worms, coral polyps, algae, flake food and brine shrimp or plankton.