Also known as Bullseye, Hatchet Fish, Vanikoro Sweeper.
Found in schools, during the day in caves, under ledges and in shipwrecks, dispersing at night to hunt for food high above the bottom, in harbours and over coral and rocky reefs.
They feed nocturnally on zooplankton.
Length - 13.9cm
Depth - ?m
Widespread Western Indian Ocean
Sweepers school during the day, but at night they float high above the bottom to hunt for larger zooplankton.
Several species are triangular shaped. Ref: https://www.fishbase.se/summary/67343