DISORDERS OF THE SWIM-BLADDER
WHAT WE KNOW AND WHAT WE DON'T KNOW
By Jim E. Quarles
30-08-99

I can't think of any problem affecting discus that is more unsettling to the owner than to enter the room and see a beautiful fish swimming upside down or with its tail dragging the bottom of the tank and it nose pointed at the sky, or head-down tail up!

See the lump from his swim bladder

When this happens it is known as swim-bladder disease. What we don't know far exceeds what we do know about this problem. Just a few methods are used to try to recover these fish. I am sad to report that in most cases that is not possible at this time.

However, that should not prevent us from working hard and doing our best to not only save the fish but perhaps learn something new to add to the knowledge about the event.

Known Causes And Some Suggested Treatments

Various factors, including sudden changes in temperatures, and other factors, such as microbial infection may be involved.

Symptoms: The fish experiences difficulty in maintaining its position or balance in the water. It may 'list' one way or the other. In some cases it will even float on its side at the surface of the tank. It may even become upside down and try to swim that way.

These swim-bladder disorders can and do occur in a variety of situations, often this happens with no warning and spontaneously in previously normal stock. Other fish in the tank may go totally unaffected. While this problem happens in all types of fish species it is most common in fancy goldfish. But in their case it is more likely due to mis-shapened swimbladders and these fish would be considered culls and would not be treated or allowed to reproduce themselves.

Since the exact cause is unknown or very poorly understood, I have a hard time recommending treatment. Here is what I do. I remove the fish to a treatment tank containing shallow water at 82 degrees F. I then add aquarium salt or rock salt to 1 gm per gallon. I then treat with a proprietary antibacterial agent for a few days.

If this fails I generally then painlessly destroy which remain clearly in distress.

General recommendations: Avoid sudden changes in the temperature of the tank water.
Maintain the cleanest possible water supply you can. Do not prolong the suffering of fish that can not be cured.

I know we all love our fish, but sometimes the best course of action is mercy.