Determine on how and where fish eat in the water column, fish food can be categorized by its source, such as natural aquatic foods (bloodworms, srimps, artemia, shellfish, algae, spirulina) and prepared foods (flakes, pellets, tablets) made from processed ingredients. Essentially, fish feed is typically specialized for specific fish species to meet particular functional requirements, such as color enhancement, nutritional fortification, and vitamin supplementation.