Dr. Johnson, I have a goldfish in a tank that I am fairly certain is dying with dropsey as I type. Last week, my husband told me he had "Ick". I started treating the water with 0.075% malachite green. I am assuming that the "Ick" infection was the stressor that possibly triggered a latent bacterial infection. However, I need to know if my treatment with the malachite green had anything to do with his inevitable demise. Any tips not in your other articles for saving the other fish in the tank? He is totally asymtomatic. Thank you so much. I am going to have a lot of explaining to do to my kids...Kelly Harbert.

Kelly Harbert

I don't relate Malachite Green and Dropsy. Malachite Green was at one time a valuable medication but it is associated with cancers in animals and people exposed for a long time, or who eat residues in tissues. So they're getting rid of it. Too, salt is a much faster remedy for Ich anyway, with a lot less stress.

So next time please use salt instead, but don't feel guilty about using the Malachite green because it did not cause the Dropsy.

Dropsy, also known as Bloater or Pinecone disease, is usually caused by bacterial invasion of the fishes' kidney.
There IS a sporozooan parasite that can damage the Kidney this way, called Mitraspora cyprini, but I have yet to see this on a necropsy.

Dropsy is, for all intents and purposes, untreatable, based on 2 years experience, using the following drugs: Azactam, Baytril, Chloramphenicol, Gentamicin, and Amikacin. I have tried a Sulfa drug, brand name Albon, and that did not resolve the problem either.

Bacterial dropsy is usually caused by Aeromonas or Pseudomonas bacteria. By the time the fish "blows up" and the scales protrude form the body, the damage to the kidney is so profound that recovery is impossible.

If you must try to save the fish, Isolate the specimen, elevate temps while elevating oxygenation, and begin injecting antibiotics intraperitoneally. You could also feed the antibiotics in a medicated feed.