What is Swim-bladder disorder?

It is a condition when the swim bladder isn't working correctly causing the fish to swim upside down. It is a widespread illness within aquarium fish. Swim-bladder is only found in bony fish.

A swim bladder is a gas-filled internal organ that helps a bony fish maintain its buoyancy.

This disease will not be transmitted to other fish within the same tank. It will be best to separate the fish from others so it can better be treated and have its symptoms observed. Giving them their own separate space will also aid in recovery.

Swim bladder disease, also known as positive or negative buoyancy disorder, is a complex disease syndrome.

Positive buoyancy disorder

Where the Fish floats at the Surface or on its side, is the most commonly presented form of swim bladder disease, especially in goldfish. The cause is overinflation of the swim bladder. If the weight of the displaced water is greater than the weight of the fish, the fish is said to be positively buoyant and will tend to float.

Negative buoyancy disorder

The poor medical condition could be due to the cause of negative buoyancy disorder, the most common cause of this problem is fluid buildup in the swim bladder.


Sometimes we see that fish floating abnormally in the tank is dead but it is actually exhibiting symptoms of the swim bladder.

Curved back

If the fish's abdomen is inflated, other organs are pushed aside, which can sometimes cause the spine to curve.

Changed appetite

Affected fish may eat normally or have no appetite at all, the fish may not be able to feed normally or even reach the surface of the water.

Distended belly

The fish's digestive process may become disrupted with this disorder, which may cause the Belly to become enlarged.

Rapidly eating, overeating, constipation, or gulping air may occur with floating foods to cause an extended belly and displace the swim bladder.

How to cure swim bladder disorder?

In order to prevent this disease

  • Keep the tank as clean as possible.
  • Feed green peas to the affected fish, feed the fish a cooked and skinned pea, (not too soft but not too firm) remove the skin, and then serve the pea to the fish.
  • Add a small amount of aquarium salt to the tank.
  • Reduce water flow in tanks with a strong current.
  • Most importantly feed the fish highly nutritious food.
  • Make sure the temperature is slightly higher than normal to aid in digestion.
  • Low water temperature can slow the digestive process, which in turn can result in gastrointestinal tract enlargement that puts pressure on the swim bladder.
  • Antibiotics may help, and for this, you'll need to visit your veterinarian.

These are some factors that will give the fish the best chance of not catching this disease.

This disorder can be due to multiple factors such as:-


Once pinch a day should be more than enough for a small fish.

Birth deformation

It is mostly seen in goldfish and bettas.

Your fish may have cysts growing in its kidneys, which will enlarge.

Environmental factors

If your fish experience upside-down swimming after a water change, this can be a good sign of environmental stress.

Water quality

Water quality should be clean and changes should be performed every two to three days.


Good nutrition provides a wide range of nutrients to maintain health.