I have had my tangs in copper power for 21 says, . I now want to do a couple of iterations of general Cure, but even after an Additional week with several water changes, using cuprisorp and a polyfilter, the copper in my QT is still registering at .47. I know I have to take out the filtration when I run GC, so .4 seems high for the copper still in the tank. Is it high? How low should the copper be before I can go to the next stage of my quarantine? Outside of a poly filter and cuprisorb, what else can I use to rid the copper in my qt. I’m using a Hanna tester. Thanks.