I wanted to get some advice/feedback after attempting to QT a copperband that died last night. I want to see what I could do different the next time. I purchased the fish about a month ago and he immediately went into QT with a 6 line wrasse. The tank is a 10 gallon with a HOB filter. Only other thing in the tank was a piece of PVC for hiding, heater, and an ammonia alert badge. I tried various foods and found that he would pick at some frozen but really went after live black worms. I fed him several times a day. Around 12 days into QT, the wrasse had a white spot on his head and I have heard that copperbands typically bring something in. So I decided to start treating with copper. I used copper power and was going to add .25 per day until I got to 2.0. When I got to .50, I went in one morning and the six line had died and the copperband was not moving much and not eating. I immediately setup another 10 gallon QT with new water and transferred the fish to the new tank. After a few days, it resumed eating the live black worms, but not eat like it did previously. I noticed that it was twitching his head a lot and darting around the tank. Also, he was breathing rapidly. I then decided that I needed to treat for parasites, so I put a dose of API General Cure into the tank. He seemed fine after 48 hours, so I added the second dose. I went in this morning to check on him and he had died. With that said, any recommendations on what I could have done differently? Thanks!