I had two axolotols that I got from a friend. A couple days ago I noticed milky mucus spots on them, and now one is dead and the other seems to be able to make it, but not have open sores. What could've caused this, and what's the best remedy to help the remaining one heal?! I haven't lost an animal to disease in years, and I don't want to start now. I did notice that the pleco I had in with them, which usually ignores them, was attached to them. The tank is the one that came with them. Any help is appreciated!!