My tank is three months old. Few weeks ago I was notice that my Midas trying to bit own tail and scratch against rocks and gravel. After few days I sow some of my fish start to breath heavy and die after next few days. All fish are eating all the time. I started dosing polyplab medic five days ago but don't see any changes. Today next of my fish died. I'm not sure if this is ich or something else. I don't see any white spots on my fish and this is why I started with something not to agresive. I prepered already quarantine tank and thinking to do cupramine treatment. Please, let me know what you are talking about my problem.