Our Red Platy is very sick

Question
We changed the water in his tank today and a couple of hours later we looked at him and he had white fuzzy stuff around his tail fins. He is not moving around well at all. He is now lying in the corner of the tank. He's in a small 1 gallon bowl. We use bought spring water to fill the bowl. Please tell me what we can do as soon as possible, because it seems to be getting worse.

Answer
Michelle,                                                    It sounds like a fungus, but you platy needs to be in a heated tank. You can try marycin 2. Just try to adjust the amount for his bowl, but I think you are going to have problems with keeping tropical fish in an unheated environment again. Good Luck,Tina