Swim Bladder Disease (SBD)

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What is Swim Bladder Disorder?

Swim bladder disease is when a betta has a disrupted swim bladder. This can be caused by overfeeding or it can occur with younger bettas when their swim bladders are not yet fully formed. This disorder is commonly seen in betta keeping and it usually just goes away by itself. It’s not contagious.

Sometimes it can be a symptom of a bacterial infection or a fin injury. If the fins seem torn or damaged, try our cure for fin rot. If the fins seem fine but the fish seems lethargic, has clamped fins or discolouration, try our cure for bacterial infection.


  • SBD is a common symptom for most betta illnesses, major or minor. It’s likely that a keeper will encounter it at some point, so it’s useful to be aware of its symptoms as soon as you own a betta.
  • If your betta does have Swim Bladder Disease, it may appear lethargic or look like it has difficulty swimming. It may wiggle on the aquarium floor or it may not move at all.

Possible Cures

SBD is usually due to overeating, but it can also be a sign of a serious disease such as tuberculosis. Unfortunately there is no way of telling for certain if it’s due to one or the other.  If your betta is in a community tank and it appears to have a bad case, you may like to isolate it to be on the safe side.

If you suspect that your fish’s lethargy is down to simple overeating then don’t worry too much — this disorder on its own isn’t life threatening. Simply feed your betta less, maybe even fast the fish for a day or two. Try giving the fish a more balanced diet. You will know then for certain if your fish was suffering from a simple case of SBD if its stomach reduces in size.

If it’s a defect in a young fish, the disorder should go as the fish grows. If the fish is having difficulty swimming, lower the water level in the aquarium (to about 8cm to 10cm) so it can surface for air more easily.

Avoid using these cures


We’ve seen it suggested online that you should add salt to cure Swim Bladder Disease, but salt should only be used for a bacterial infection.


Some people also suggest feeding your betta a pea if you think it has SBD. However, a pea should only be used for curing betta constipation. Being high in fibre, the pea is like a laxative. SBD can be a symptom for many illnesses, and is a main sign of betta constipation. However, if your betta has SBD, it doesn’t necessarily have constipation.