Alright here is the story, I bought a 5 inch fancy oranda goldfish. Unfortunately he had a wound on his upper dorsal fin when I had bought him, but after having him for a few days I grew attached and didn't want to return him. Being ill-experienced I bough an additional fish (a Panda Oranda goldfish), and at first they were fine and swimming together in a 20 gallon tank.... but soon enough the panda realized my first fish had a wound and starting picking at it and making it worse. I even bought another tree so there were one for each of them...
After about 3-4 days I decided that this could no longer go on, due to the fact that my first fish constantly swam in the front corners of his tank to escape from being bitten by the Panda. I bought a completely separate 10 gallon tank, filter, oxygen pump... etc. for this 3 inch panda fish. About a week after he was introduced to the tank he started showing signs of ick. Like I said, I wasn't sure what was happening, and I asked my neighbor who has fish and aquariums what was wrong? He said it was ick, and provided me with the treatment.
Within the first day for treating for ick I noticed that my panda goldfish had what looked like a soar on his mouth. I went to Petsmart and asked them what to do, and they said that they thought he might be getting a bacterial infection, but that I couldn't use the ick med. and an antibacterial med. at the same time, because it would stress the fish out. So i finished the ick treatment.
By the time the ick treatment was done the fishes mouth had gotten A MILLION times worse. I came to find out he had mouth rot! I cleaned his tank and then waited a day and a half before adding Melafix and attempting feed him antibacterial food pellets. I started treating him and the swelling on his face had gone down but his mouth still remained horribly shredded it looked, and then half of his face and stomach started turning black and he started loosing his scales! I have no idea what is wrong. From what I can tell it looks like ammonia burn, but I've been keeping his tank so clean that I don't think that's even possible.
I do water changes every few days to a week just because I am so worried about this fish. He was fine when I got him, and I'm just confused on what I am doing wrong. I've tested his water and the test strips say he should be doing just awesome, but he looks completely the opposite. I just don't know what else I can do to help this fish. Any advice would be good. I want my fish to be healthy and happy