The Triangular Butterflyfish, Chaetodon sp, has a grey colored body and darker chevron markings on the side, a bright yellow head with three reddish-brown bar including one on the snout, and a bright yellow submarginal band on the tail. They are peaceful and can be kept with other peaceful fish, but may become aggressive towards other Butterflies with a similar pattern or coloration in smaller tanks. Since they are more sensitive than most other Butterflies, they are recommended for experts only.

They are also not reef safe since they will nip at and eat soft corals and stony polyps as well as ornamental shrimp, tube worms and anemones. Diet should include a variety of mysis and vitamin enriched brine shrimp, spirulina, nori, seaweed, marine algae, and algae based foods, 2-3 times daily.