I've had my sailfin tang and kole tang in a 37 gallon quarantine tank and I've been treating them for ich with cupramine for 4 weeks. My sailfin tang still looks like he has ich on his tail. I've kept the level at .50 the whole time and even brought it up to .60 this last week. How is it possible he still has ich?? Could it just be permanent damage on his tail from having ich for a long time or something? It's only on his tail. And the kole tang has been clear for 2 weeks now. Should I keep treating? There's no live rock and only a few specs of sand left from when I scraped the sand out and couldn't get it all. Any suggestions? Thanks for help in advance