Okay guys, I seem to got myself in a bind again ^^;
My friends friend fish seem to have contracted some type of fungus. He bought them from the evil Petsmart down the street where they always have unhealthy fish. He put them in with his healthy fish, and now 18 have died :( (He used the medicine Pimafix and Melafix, because it was on the fish as well, which did nothing) There are only 4 left, which are staying at my house until they get better. As soon as he took the fish out, his tank went back to normal water quality. But now, overnight, the hospital tank they are staying in has gotten infected, now having massive amounts of gunk in the water, walls and ground. On the ground its in piles of goo. Its bleh. The fish are not acting like normal mollies and swim EXTREMELY weird. They eat regularly...but they are still not completely better. My betta tank kept getting a fungus in it and I eventually killed it with a heck a ton of salt.
What do you think I should do? I am kind of stuck xDD