There is Magenta stuff, Purple stuff, Pink stuff and blue.. etc. For copper at 0.2 and mostly everything else is fine with salt at 3400. What would be good to maintain the copper. When I opened it on day 1 by day 9 it is clear and crystal. Now it is getting stains again. I cannot drain the pool all the way and maybe just a metal sequestering agent will do. Which one do I need?