Rane

Hi, I have a 100 gallon planted tank with a school of 12 cardinal tetras, 3 rainbow fish, and 4 zebra danios.

My tank has only been set up for about two or three months. I used the bio media from my old tank, so the tank has never had any ammonia or other measurable toxins. Nitrate is at 20ppm. PH 7.5 My substrate is boiled miracle grow topped with gravel.

Last week I noticed that one of my Cardinal tetra's had developed dropsy (scales sticking out; looked like a pinecone). Then another. Now a third. The Cardinals seem to be the only species affected (so far). Strangely, their appetite and activity does not seem to be affected.

The only information I can find suggests that I'm probably not going to find any obvious answer. I don't really feel like throwing a bunch of anti-bacterial medication at this without even knowing if that's the problem.

Perhaps someone can suggest a plan of attack? Or some sort of direction I could take? Should I remove the sick fish?

Any pointers would be appreciated.

DishyFishy

I've never actually dealt with it myself, but I would say you should quarantine b/c Dropsy can be a symptom of other problems, such as bacterial or parasitic infection.

Diana K

You could try putting the Cards in a quarantine tank and adding some Epsom salt. This can help them get rid of the excess fluid in their body, but it does not treat the underlying problem.
Unless you can figure out what is causing the problem (Bacteria, virus, other) then treating is hit or miss.

Rane

Thanks for the replies. Kinda' what I was afraid the situation might be. I removed the affected fish and did a 70% water change. I'm going to try and do daily water changes for the next few days and see if any more fish develop problems.

DishyFishy

Any improvement in the little guys?