For day-to-day feeding, most pet owners prefer to feed betta fish freeze-dried food. These fish actually prefer live food, but freeze-dried food is less expensive and more readily available.
In their natural environment, betta fish eat mosquito larvae. They particularly enjoy red mosquito larvae, known as bloodworms. Live brown worms can be fed to betta fish, but they may introduce harmful bacteria or disease to the fish. Betta fish also enjoy freeze-dried or fresh brine shrimp. Frozen food is a good alternative to live food. Betta fish stop eating freeze-dried food once they have had their fill, but they continue to eat if live food is available.