HI, WELCOME TO FISHLORE!
Are the scales sticking out like a pine cone? If so it sounds like dropsy. This is a kidney problem, and is hard to treat. Some say if you seperate and treat with epsom salt, then an anti bacterial like maracyn-plus, or maracyn-two it might help.....for the epsom salts, start with 1 tsp / gallon, and you can go up to 1 TBL/gallon. I wouldn't use this for more than a few days....usually if it is going to help it will do so within a day or two...once the water is drawn out, the meds can work and the fish is less stressed...
However, like I said, it is REALLY hard to treat, and just like in humans, once the kidneys stop working, it is hard for them to recover.
Good Luck, and I hope your fish recovers....Let us know!
