Do Betta Fish Eat Other Fish. Betta fish have unique personalities, and some are very laid back while others are extremely aggressive. They will kill other fish if they find them.
They will kill other fish if they find them. Betta fish have very short digestive tracts and do not process fillers like corn and wheat very well. For example, anything with bright colors They don't breed as quickly and easily as other snails and help eat algae and other debris from the tank.
It also seemed like some of the cases were similar to yours, in which the betta seemed to live peacefully with.
As with most fish tank dwellers, they will eat anything small enough to fit in their mouth, including small fish.
If the betta killed it it would still be in the tank. Most bettas sold in pet stores can be kept in small fish bowls, sometimes with plants and even other fish (depending on the species). Betta fish are Anabantids, which means they can breathe the air above the water through their mouths as well as obtain oxygen from the water through their gills.