Quote Originally Posted by Midnight View Post
Can all the water chemistry being off bind up the copper and it's just going to show up later when the water is balanced maybe?
Low pH can dissolve metals, which may then reappear as stains when the pH and alkalinity are increased. Adding HEDP prior to 're-balancing' can temporarily keep the metals in the soluble (non-staining, but also non-filtering-out) form. The CuLator bags can remove SLOWLY remove metals from pool water but ONLY when the metals are in the soluble form.

If the metals are not actually removed from the water, they will began to reappear. Depending on a number of factors, metal can reappear as debris collected on the filter -- this is a highly desirable outcome. When HEDP is used, the filter should be run 24/7, so that as the HEDP breaks down and releases the metal, there is an improved chance that it will be caught as particles on the filter.