Siamese fighting fish have upturned mouths and are primarily carnivorous surface feeders, although some vegetable matter may be eaten. In the wild, they feed on zooplankton, crustaceans, the larvae of mosquitoes and other water bound insect larvae. Typically, commercial betta pellets are a combination of mashed shrimp meal, wheat flour, fish meal, brine shrimp, bloodworms, and vitamins. These fish will also eat live or frozen bloodworms, mosquito larvae, brine shrimp or daphnia.

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