I am sorry to hear about Birdy. Swim free.

I am worried about the other fish.

* Can you tell us the test results for ammonia, pH, nitrites, and nitrates?
* Any other changes in behaviour or appearance?
* Anything at all new in the tank including decorations, medications, dechlorinator or water chemicals?
* When were the last three waterchanges and how much was changed?

Dropsy can often be related to a cycle in progress, elevated nitrates, or missed waterchanges in a stable tank so those questions should help investigate.

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