The purple tang (Zebrasoma xanthurum) is a beautiful member of the tang family. It is also commonly called the yellow sailfin tang and the blue surgeonfish. This species is found in the Red Sea and Indian Ocean. Like most tangs, they are herbivores, feeding mainly on algae. Adults of the species can reach a length of about 10 inches (25 centimeters) and are found at depths of up to 65 feet (20 meters). This is a popular fish in the aquarium hobby due to its bright purple coloration.