Bettas (pronounced bet-tah, not bay-tah) are well known as fry hunters. If you do not want your guppys, platys or swordtails to overrun the tank, get a male betta to share the tank with them.
Bettas are carnivores in the wild and eat live food most of the time. They feed on small insects, larvae and crustaceans at the surface of the water. They need a high protein diet and people who expect them to eat roots of plants and algae are just starving them to death.
Once a betta realizes there are fry in a tank, you will him them all over the place looking for snacks.
Bettas will live fine with other fish, the only ones they fight with are other bettas. Most of the time a betta is on the receiving end of harrassment from fast moving fin nippers such as barbs and tetras.
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