Clorox Pool&Spa pH Down lowers high pH that can cause itchy, irritated skin and scale formation on your pool surfaces. The granulated formula simple to apply and dissolves fast, and the easy pour application bag makes this a simpler, faster solution compared to Muriatic Acid. High pH can cause dry, itchy skin and hard-to-remove scale on pool surfaces. Use this pH decreaser as needed to achieve a suitable range of 7. 2 to 7. 6 to keep your water swim-ready and clear. For use in both traditional chlorine and salt chlorine pools. Test and balance your pool weekly with the Clorox Pool app to maintain clear water, longer lasting equipment, and comfortable swimming. Maintaining proper pH of 7. 2 to 7. 6 is both important and easy. Important, because if pH is too high, chlorine cannot effectively sanitize and disinfect your water and water will irritate your skin and eyes when you swim. If pH is too low, corrosion can occur and the pool water will irritate your skin.