Koi food typically contains high levels of protein, which is essential for growth and development, and also contains certain essential amino acids, vitamins, and minerals. The pellets or flakes are also usually slow-sinking, which allows koi to feed throughout the water column and helps to improve digestion. In addition, koi food often contains added antioxidants, Probiotics, and enzymes, which can help to support a healthy immune system and digestive system. Some koi food also containsifiers and color enhancers to help bring out the natural colors of koi.