I've had no problems with my tank. Water quality is fine, ph fine, nitrate 0, amonia slightly above 0, nitrite 0. The **** carbon was the problem. I used it to keep the water clean, but had no clue that would be a big effect to the fish within a week. All the fish in the tank seems to be more active and all are eating well. Fox face looks 5 x better, however the powder brown has cuttle flower now. I don't think i've ever won a fight against that. The only way to get rid of that is to cut it off right? I've tried to QT my french angel once that caught black cuttle flower and ended up cutting off parts of the fin's that it was attached to. It was strong enough to survive through that and lived for a few months later, but went away on me. i've read somewhere on a web site stating that magnesuim would help prevent HLLE correct?