Habitat:
First and foremost the system should be as large as possible. These Butterflies live on the outer reef margin and are free-ranging fishes, covering large areas. Also, they need physical cover to feel secure. Hemitaurichthys B/Fs are quick to duck into coral, rock hideaways in the wild; they need to feel they can do the same in your system.
Due to size and eating habits these B/Fs are fish-tank only members; they will pick apart nearly every invertebrate in time.
Hemitaurichthys spp. are zooplanktivorous, picking out small swimming or suspended animal matter as the currents bring them their way. In aquariums they quickly learn to accept all forms of meaty live, frozen, freeze-dried and flake foods. Take care that yours get adequate volume of feed; these are large, active animals that forage for food all during daylight.
HTH
Mike