All fish / Chaetodontidae

Schooling Bannerfish

Heniochus diphreutes

Also known as schooling bannerfish, pennant butterflyfish, false moorish idol, poor man's moorish idol, schooling coachman, bannerfish, heniochus, red sea bannerfish, pennant coralfish, ผีเสื้อโนรีครีบยาว, ムレハタタテダイ, kepe-kepe monyong

A white, deep-bodied butterflyfish with two bold black diagonal bands, yellow dorsal and tail fins, and a long white pennant trailing from the dorsal fin. It looks much like the Moorish idol but is far hardier, and in the wild it gathers in large midwater shoals feeding on plankton, which makes it one of the easier butterflyfish to keep in groups.

Care at a glance

Care level

Moderate

Temperament

Peaceful

Adult size

18 cm

Temperature

23 to 27 °C

pH

8.1 to 8.4

Smallest tank

500 litres

Keep as

Small group of 3 or more in a large tank, or singly

Diet

Omnivore: mysis, brine shrimp, chopped seafood, marine flakes and pellets, algae-based foods

Swims

Middle of the tank

Lifespan

5 to 10 years

Water

Marine (saltwater)

Wild range

Indo-Pacific and Red Sea, from East Africa to Hawaii, Japan and Australia

Breeding

It scatters pelagic eggs in open water, and the larvae drift as plankton for weeks. Captive breeding is very rare and not practical in home aquariums, so almost all fish sold are wild caught.

Good to know

Easily confused with the longfin bannerfish (Heniochus acuminatus), which has a longer snout and fewer scales; it is safer with corals than most butterflyfish but may still pick at soft corals and tubeworms. Needs plenty of swimming room as it grows to around 18 to 20 cm.