Swim bladders fill with air and allow a fish to stay afloat rather than sinking to the bottom of the tank. Fish regulate these bladders according to where they are and what they want to do. Any damage or disease in the swim bladder causes difficulty with swimming and may be fatal if not treated in time.
Make sure the fish has swim bladder disease. A fish that swims awkwardly, floats belly up while still alive, lays on the bottom of the tank or has an enlarged abdomen may have swim bladder disease.
Isolate your fish in a different fish tank, with pump and filter. This protects the fish from the stress and possible abuse of the other fish. Use a pump and filter in the new tank to ensure good water quality.
Increase the fish's nutrition. One case of swim bladder disease is poor nutrition, so increase feedings to treat the fish. Pre-soak flake fish food or use gel-based, frozen or live food to make eating easier for the fish.
Thaw several frozen peas and feed them to the fish every day. Studies suggest that peas help break up whatever is causing swim bladder disease. Continue with any treatment until the fish has improved in health, and maintain better nutrition to prevent future swim bladder disease.
Possible causes of swim bladder disease include trauma, genetics, cancer and diet.
If swim bladder disease has progressed too far it will prove fatal despite treatment.