The rainbow shark (Epalzeorhynchos frenatum) is a species of Southeast Asian freshwater fish from the family Cyprinidae. It is also known as the ruby shark, red-fin shark, red-finned shark, rainbow sharkminnow, green fringelip labeo, whitefin shark and whitetail sharkminnow. It is a popular, semi-aggressive aquarium fish.

Rainbow sharks are picky herbivorous and omnivorous eaters but are primarily consumers of algae in the form of flakes. They also eat live foods, such as insect larvae, tubifex worms, periphyton, crustaceans, phytoplankton, zooplankton and aquatic insects. Diet also include lettuce and spinach.

Rainbow sharks are compatible with barbs and rainbowfish, which are upper- and middle-tank dwellers. They can also live with danios, loaches, plecos, rasboras, and gouramis.