I know you are heavily invested going the Copper route but I wish everyone going through Ich starts reading about Hyposalinity.. Its the easiest treatment out there for ich and flukes.. Taking out Corals and Inverts might be easier than taking out all those fish.. Setting up a 20g tank for all the corals and inverts should be enough instead of managing 2 separate 40g breeder tanks, dealing with cycling, changing water, parameters management etc .. Again, my intention is not to have you re-strategize, but for anybody reading this thread and struggling with ich in DT, do spend 30 mins reading about Hyposalinity.. From near death to spotless and healthy fish, I was able to achieve that in my Display Tank in less than 3 months.. And its not as hard as somebody might think.. with an ATO, maintaining 1.009 salinity is the same as maintaining 1.026 salinity for 3 months! Now of-course I can re-introduce ich, but hope that with ich management, I can keep that at bay!