Swim Bladder Disease in Aquarium Fish

The swim bladder is an organ found in the abdomen of most fish. It helps a fish control its swimming depth. By adjusting the amount of air in the bladder, the fish can move up and down. Swim bladder disease affects the fish's buoyancy and can be fatal.

  1. Causes

    • Swim bladder disease can be caused by food impaction. Using dry foods that expand when they absorb water can lead to impaction in the digestive tract. The round body type of goldfish makes them especially susceptible to this condition. It can also be caused by viral and bacterial infections that inflame the lining of the swim bladder. This makes it difficult for the fish to control movement of gases in and out of the bladder.

    Symptoms

    • A fish with swim bladder disease will have difficulty swimming, especially moving up and down in the aquarium. The affected fish might stay around the top of the tank and may float upside down. If a bacterial infection is the cause of the swim bladder disease, red streaks may appear on the fins and tail.

    Diagnosis

    • If your fish has recently been floating upside down in the aquarium, take it to a veterinarian for a physical exam. In addition to an exam, X-ray technology might be employed to diagnose swim bladder disease.

    Treatment

    • If the disease has been caused by a bacterial infection, try an antibiotic food. If your fish isn't eating, move the fish into a small tank and treat the water with an antibiotic. Carefully watch the other fish for signs of the disease. If the swim bladder disease is due to food impaction, increase the water temperature to 75 to 80 degrees Fahrenheit and feed the fish a single canned or cooked pea that has been crushed. The pea might help push other food through the digestive tract. Discontinue using floating pellets or flake fish food while trying the pea treatment.

    Prevention

    • Carefully select your fish at the pet store. Make sure any fish you purchase is swimming and floating normally. Before introducing a new fish to an established aquarium, keep it in a separate tank for a month until you are sure it is healthy. Supplement your fish diet with peas or other green vegetables, especially if you are raising ornamental goldfish. Use sinking pellets that don't absorb as much water instead of floating pellets or flake food, especially with goldfish.