The blue hippo tang is a species of surgeonfish with many common names, including the royal blue tang, regal tang, palette surgeonfish, and “Dory.” Juveniles are bright yellow with blue spots. Like all surgeonfish, this species has scalpel-like spines along the top and bottom of its body and a sharp, venomous spine at the base of its caudal fin, or tail fin, to protect it from predators. Adults are omnivorous and feed on plankton but will also graze on algae that grow on coral reefs. The blue hippo tang is essential to keeping the coral reef healthy by keeping algae in check.