It seems you have some very nice trick to fix my pool water!

Maybe copper is really binding to CalciumPhosphate and since my DE filter is really good, I can filter out CaP in 48 hours.

What I do not understand yet, is your sentence "....to extract the phosphates with the calcium". How should I fix phosphate level now that the Cu level is dropping. I have a long way to go, but maybe I can survive with 1ppm of Cu and low PH?

Thanks!