So I have two problems. One my Betta has been sick with tail and fin rot for quite some time. It seemed to be going away but now it's back and I don't know what to do. I've been using Marcyn 2 for quite a while. Problem 2 (first things first I should tell you that my Betta is actually pretty docile but It's been alone for a year and I've finally been able to upgrade my tank) I bought two neon tetras and a Glowlight tetra (as an experiment) to see how my beta would react to them (of course ...