ProTeam Spa pH Decreaser reduces the pH of water in spas and hot tubs. pH levels should be maintained between 7.2 and 7.6. When the pH levels exceed 7.6, the water can become cloudy and conditions are favorable for scale to form. Additionally high pH may cause sanitizers to be less effective in the water. This product is compatible with chlorine, bromine, biguanide, silver-mineral, and ozone-treated pools and spas.