Odonus niger

Odonus niger, commonly known as the Red-toothed triggerfish, is a medium-large triggerfish, often seen in the aquarium hobby.This fish has a very variable color, ranging from light blue to dark blue to purple. They have long lobes on the caudal fin which are usually bright blue like the edge of the dorsal and anal fin. When growing older, their teeth turn red and their face because lighter, variating from the more common greenish-yellow, to lila. Combined with the unusual triggerfish shape and graceful swimming, a lot of people are attracted to this fish.

Remember it isn't reef safe though! It mainly feeds zooplankton and sponges, but might damage corals as well. It can also be agressive to other fishes, so make sure you pick the other fishes with care!