Hi I have three 4-5 inch goldies in a 30 gallon tank. Two are commons and one is a comet. They've been in there since Oct. The filter is a HOB. They get weekly 30-50% water changes. No heater. Water temp is normaly in the high 60s. Diet is pellet and fresh veggies. Water paramters test fine, PH is high though. Tank mates are a nerite snail and mystery snail. I know these guys are in a tank to small for them, I've been looking for a pond, but then it got too cold to move them to an outdoor pond. I also rescued them from someone who was going to dump them in a river, and prior to living with me they all lived in a 10 gallon tank. However I'm here because one of the commons has developed an issue. About a month ago I noticed one of them seemed to have a little bit of swollen eye, but everyone just told me I was crazy. So I just figured he bumped it or I was losing it. I didn't think anything more of it as it never got worse. However when I went to do there water change this Sunday I noticed he's had a lump under his gills on the same side that his swollen eye is on. This morning I checked on him on the way out to work his scales have started to pine cone, but it's only a small lump on his side. Rest of his body isn't swollen or pineconey. He also has been more lethargic then the other two the last few days. He still gobbles down food too. Is it dropsy? I've done some searching and while his syptoms seems to match Dropsy, this only effecting a small portion of his body leading me to belive something else is wrong with him. When I did his water change I did add salt to the water. I don't know why I didn't think of it, but I'll add a heater tonight as well. I do have a hospital tank I can move him to but it's only a 10 gallon. Any other advise for me? Thanks in advance!