AQUA PLUS pH Plus is amongst the most important products of all pool chemicals, as they help control the pool water pH, alkalinity, calcium hardness etc. Your pool or spa needs to be maintained at a pH of between 7.2 – 7.8, a slightly acidic condition. Operating within these parameters will prevent damaging your pool equipment and ensure that your pool is sanitized throughout. AQUA PLUS pH Plus can be used to increase either the pH or Total Alkalinity. Use a test kit to determine both the pH and Total Alkalinity of your pool.