To add CYA, put solid/granular CYA in a sock (a tube sock, pantyhose, or a skimmer sock all work) and place in the skimmer basket, or suspend the sock front of a pool return. If suspending near a return jet, ensure the sock cannot rest against the pool surface since the granules are acidic and could potentially discolor the surface. After soaking for about 30 minutes, squeeze the sock periodically to help it to dissolve faster. Leave the pump running for 24 hours and don’t backwash or clean the filter for a week. Test and dose chemicals in your pool as if the amount of CYA you added is already in the pool. A day after the CYA has fully dissolved from the sock, you can retest your CYA and add more if necessary.
