Tonight I came home and noticed that one of my USD cats was out swimming around in the tank. I had recently added some plastic floating leaves, so I thought maybe it was happy that there was something on the top of the water. As I was looking at the fish I noticed a couple boil-like things on it. They were very small. One of the gill areas also looked raw and maybe like there was some pinkish skin showing and I don't think its eyes look the same. They seem maybe a little more pronounced than I remember them first being. Maybe a tad bit cloudy, too. Ever since I have got this fish it has had a very fat stomach. The guy at the lfs said that it had been eating well, but when I went to hunt for the other USD cat I found it had a fat stomach-looking thing starting on one side of it. This is the first time I've seen these fish out swimming since I've gotten them. They like to hide upside-down in PVC pipes and a fake castle and a round rock thing, so I saw them a little bit, but not enough to see a problem. I didn't think much of it when they were hiding because I had read they liked lots of hiding spaces, which the tank they were in at the lfs had one small dinky plant, so I figured they were hiding because now they had actual places to hide.
This pic kinda shows its eye and stomach area:
You can see the big stomach well in this pic:
I also noticed the water was a little cloudy, so I am about to do a water change. Probably about 20-30%. I have 0 ammonia, nitrates at 5, nitrites and 0, pH is 6.6, water is 79 degrees. Is there anything I should treat or what should I do?
Edit: Okay, I just realized I had some medicine that treats open sores (which is what the one fish looks like it has) and internal swelling, which now I'm guessing both fish have since the one now has the new boil-thing. The medicine is Neomycin by Aquatronics. I'm going to treat them tonight, right after I do the water change.
