i got the tetras from a friend that owns a petshop. A couple different kinds, i think black phantoms got the cotton mouth, had a couple of Serpae, they just died, and have 2 of those left, one has a white mark on his mouth which will prob turn into cotton mouth and he will die too. Also have a couple of neon tetras, they have been doing ok, only 1 died. To be honest these fish problems are really getting the best of me lately and stressin me out.