Okay, so my large Silver Dollar seems to be all healthy again. He got some funk and almost died about 2 months ago. Spent 10 days on his side on the bottom of a bucket (with filter, heater, and air stone), before he started to get better. All the ulcers are now healed over, and he is eating normally now. My problem is that he hates the 20 G tank..don't blame him since he loved moving around the 55. He really doesn't move around much, just hangs in the back corners by some plants. I have been reluctant to move him back to the 55..didn't want to jinx things..and have him backslide. If I move him back, the 2 smaller ones would have to go with him. Should I leave well enough alone? Should I move some of the other fish from the 55 to the 20 if I move the Silver Dollars? Any advice would be appreciated. I feel sorry for this fish, he has been through the wringer.