Originally Posted by
Lucky098
He might have bloat. I think sometimes fish can catch disease that are in regular tap water. One time I got a strange algea in my tank and it came right after a water change... Ive also noticed my tank has a strange smell to it twice a year. I've found that it was due to water testing that the city did during those times.
Get your fish on a medication that takes care of bloat. Make sure the water is warm during this time and try not to dirty his tank up too much with left over food. When fish get sick, its best not to move them around too much. If you can, exchange water out by scooping out a couple cups at a time while you are medicating the fish.