Bloated Fancy Goldfish

Question
On three occasions now my two year old Fancy Goldfish has bloated to the point of floating upside down. We have an 1100 gallon indoor pond.  There are about 10 other goldfish. All three times I have corrected the condition with Epson salt in small tank. Sometimes he is fine for a few months but other times only a week or so. What can cause this? What can I do? It's obviously not the tank size and this pond is filtered.

Answer
Hi Linda,

When the Goldfish bloat, do the scales stick out like a 'pinecone'? If so, that's dropsy. Dropsy can be caused by various infections, but the pineconing is characteristic of it. The scales stick out because the kidneys fail, meaning that liquids cannot be processed into waste (urine.) The excess waste piles up in the body, causing the scales and eyes to stick out.

Goldfish are not too tolerant to salt, and the Epson may have treated it temporarily/reduced the symptoms. Dropsy is usually caused by a bacterial or viral infection of the internal organs. This can be due to poor water quality or lack of maintenance. Make sure you are performing regular water changes in your pond. A general maintenance routine should be 10-20% of the water changed every week.

Dropsy can be treated with an anti-bacterial remedy or a broad spectrum medication for pond fish. These are available at your local fish store.
Before you put in any medication, perform a 30% water change first, and remove any carbon from the filter. Remember to follow the package directions carefully!

If you have any more questions about your Goldfish's sickness, don't hesitate to ask me!

Good Luck, and Happy Fishkeeping!