Possible Bacterial infection in a goldfish

Question
Hi,
I have a 50 gallon tank with a few gold fish and a pleco. Recently i have had a problem with cloudy water. I have been trying to feed less at each feeding. I also added another filter to the tank hoping to clear things up. Water changes and vacuuming the gravel has not helped much. Once I finally cleared up the water (I do  believe my tank is overcrowded) i noticed one of the comets had a swollen abdomen. I have set up "hospital" tank with an established filter. It is a 10 gallon tank. I added 1/4 teaspoon of Epsom salt and have treated the tank with tetracycline. The fish does have the "pinecone" appearance with no open sores. After the Epsom salt he does seem to be feeling better.
I have read that once they have these symptoms they usually do not recover. Is this true in your experience? Please advise me as to what else I can try to do to help this fish.
The others in the tank appear healthy, i am continuing to monitor them.
Thanks in advance for your help.


Answer
This "pinecone" appearance is a symptom of Dropsy. Yes, Dropsy is hard to cure because there is no definite known cause. If your fish is no longer bloated and cured I would maybe think had a constipation issue more than Dropsy. Epsom salt is a mild laxative and works well in clearing up the constipation problem. If it was dropsy things wouldn't of cleared up as well. All that matters now that the symptom is cleared up, is that you keep your water clean and continue to feed your goldfish a proper diet, so they stay healthy. Any other question feel free to ask. :)