Well my freind has 2 guppies in a 3 gallon tank. She said that there was white foam stuff hanging off of it. i imidetly knew it was fungus. She said she was using tetra parasite guard. i told her to ask her parents to do a 50% water change. i also said to add salt that was not idized to the tank. I told her to add one tea spoon of salt per gallon. I also said to buy test strips. anyboudy Know anything about it. It was hanging off the fishes butt. any other ideas to help treat the fish.