So, yesterday it all began. It all hit the fan . I went home for my lunch break, and found my calico moor hiding out in my decorative vase. I monitored him while i rode my excercise bike. The longer i watched him, the crazier things got. He was swimming around crazy, and nosediving into the gravel. Then he would stop swimming and go belly up for a while, then he would lie on the bottom of the tank on his side. I quickly scooped him out and moved him from my 55 gal tank, to my 10 gal hospital tank. 
I called my husband and told him to pick up some frozen peas, as i assumed the problem was swim bladder related. When he got home before me, he found the moor swimming happily while the other 6 goldfish (still in the 55 gal) looked to be on the brink of death. We do water changes religiously (weekly), test our water at least bi-monthly if not more, and never see any problems like this before now. We have 3 dojo loaches, a pleco, and 6 snails that are donig great. So we now have 7 goldfish swimming happily (but cramped) in our hospital tank, while both of us and the fish specialists at our local stores are baffled. Our ammonia levels and nitrite and nitrate are all testing fine. The ph is a little low and our water slightly acidic. But, they have always been at these levels and the 10 gal reads exactly the same. I work at a vet office (who sadly has no real dealings with aquatics) and he said it sounded bacterial. Should i treat the tank with melafix (is it safe for the snails and dojo loaches)? And what can be done to keep my hospital tank from nosedivng into mass chaos as well? Can anyone offer any real advice or have dealt with this before? I consider myself to be a very enthusiastic aquarist and i would really love to save all of my fish, and my tank which was my christmas present from my husband. Help!
I called my husband and told him to pick up some frozen peas, as i assumed the problem was swim bladder related. When he got home before me, he found the moor swimming happily while the other 6 goldfish (still in the 55 gal) looked to be on the brink of death. We do water changes religiously (weekly), test our water at least bi-monthly if not more, and never see any problems like this before now. We have 3 dojo loaches, a pleco, and 6 snails that are donig great. So we now have 7 goldfish swimming happily (but cramped) in our hospital tank, while both of us and the fish specialists at our local stores are baffled. Our ammonia levels and nitrite and nitrate are all testing fine. The ph is a little low and our water slightly acidic. But, they have always been at these levels and the 10 gal reads exactly the same. I work at a vet office (who sadly has no real dealings with aquatics) and he said it sounded bacterial. Should i treat the tank with melafix (is it safe for the snails and dojo loaches)? And what can be done to keep my hospital tank from nosedivng into mass chaos as well? Can anyone offer any real advice or have dealt with this before? I consider myself to be a very enthusiastic aquarist and i would really love to save all of my fish, and my tank which was my christmas present from my husband. Help!