Yellow fins, black triangular
      side stripes on the white body. A vertical black stripe on the
      eyes.

A fish with
      vertical stripes on whitish body, orange back side
Redbacked butterflyfish

Blackbacked butterflyfish

( Chaetodon melannotus )

Yellow fins and the nose, black triangular diagonal side stripes on the white body. A vertical black stripe (a kind of mask) on the eyes. Pairs of these butterflyfish often swim in small deep 0.5 - 3 meter. They feed on soft corals which you see at this photo. Size - 15 cm.