The fish color is one of the most important qualitative properties in aquaculture. Pigments of diets
are responsible for creating a wide range of color in aquatic animals. Although, the pigments are
known as the color changer in fish, other functions are attributed to pigments, such as antioxidants,
growth promoter, survival and reproductive effects in fish. In this article sources, amount, stability,
structure, variety, performance, digestibility and changing of carotenoids in aquatic animals were
studied. Moreover, some new structures of carotenoids in Salmonids, Cyprinidae, and Ornamental
fish, Crustaceans, Sponges and Clams were introduced. Finally, the role of carotenoids in fish and
their effects on reproduction, fertilization and larval growth rate were discussed.