Stain Drop No.2 Copper and Scale Stain Remover, 5 lb, C005507-CS77C2

Stain Drop No.2 is a 5 lb stain treatment for removing copper staining and scale from pool surfaces.

Know the stain before you treat it

Stain Drop is sold as a numbered range because copper, iron and other stains do not respond to the same chemistry. A blue green or dark blotchy stain on plaster can be copper, and it can also be something else entirely. A stain identification kit takes a few minutes and tells you which product to reach for, which is cheaper than working through the range one container at a time.

Balance first, treat second

Stain treatment works on balanced water. If the chemistry that put the metal on the wall is still running, the stain comes back within weeks. Get pH, alkalinity and calcium in range and deal with what is introducing the copper, whether that is a heat exchanger, an ionizer or a copper based algaecide, then run the treatment.

Dosing

Use the dose rates on the container label. They are set by pool volume and by how heavy the staining is, and the label also covers circulation, filter handling and any hold on the chlorine level while the product works.