siamese fighting fish buy onlineFoodThe Fighting fish is sometimes described as a carnivore. In my statement, it is an omnivore with a choice for animal based food. In an aquarium, I recommend that a good first-class Betta food be used as the fundamental diet, and this should be varied with the addition of the occasional feeding of live food like mosquito larvae of daphnia. frozen food like blood worms also are good. WaterRainwaterRainwater is usually used. Some people use it effectively, but not all rainwater is safe for fish.