I have two bettas, a regular store bought one and a black crown tail. I feed them

[roxylee11782]

the same, keep them apart..? change water every week like I should. But why is it that my regular betta keeps having swim belly? He would float up the water and have no control over his swimming at least twice a week. The crown tail betta never does this. Is something wrong with my regular betta?

[Pawprint]

Store bettas often have health issues due to incredibly poor conditons when they were in the store.

As for the belly issue...

This is where the swim bladder, which controls the bouancy of the fish, becomes affected with something, and the fish can no longer control his bouancy. This causes him to float and sink at the same time.

First of all, PEAS! Yes, peas! Peas have been proven to help fish significantly with swim bladder illnesses. Take a few peas straight out of the freezer, run them under hot water until they soften, then peel of the skin. Feed these to your fish.

If this doesn't work, fast your fish for three-four days. Sometimes this can help. Don't worry, fish can survive longer than a week without food.

If all fails and you are seriously devoted to your fish, some marine vets will do surgery for your fish. These vets do X-rays, surgery, general anesthesia, even cancer chemotherapy on fish.

Good luck. =)