DescriptionpH Decreaser for hot tubs lowers the pH and Total Alkalinity (TA) of spa water. Helps to prevent the buildup of harmful scale on hot tub equipment, including heater elements. Reduces eye and skin irritation caused by high pH and TA levels. Balanced water can improve the effectiveness of sanitizers. Fast-dissolving form for spas Lowers TA Lowers pH Product notes: Check spa water with test strips to achieve balance. Adjust Total Alkalinity (TA) first, then adjust for proper pH range. Proper TA will buffer pH, preventing pH fluctuations. Contains 100% granular sodium bisulfate (also referred to as dry acid). Sometimes called Spa Down.