I just bought 4 Corys just a few days ago. When I fed them tonight, I noticed that one's eyes were bulging. I immediately scooped him out and put him in a salt dip. I watched him for a little while and came to the conclusion that he has dropsy. He is having trouble swimming. I added 1 tsp/gal. to my 20 gal. tank to try to prevent the rest of my fish from having problems. What else can I do? Should I also up the temp? I have never dealt with this disease before and all of a sudden I have lost two fish and possibly one more. Please help.