In The Swim Pool pH Reducer - 6 Lb. Pail
This granular pH reducer is safer and easier to store than liquid muriatic acid.  Add pH Minus whenever the pH rises above 7.6.  Granular Sodium Bisulfate.  Initial Dosage: 15-30 oz. per 10,000 gallons.  10 lbs. pH Reducer is equivalent to 1 gallon of muriatic acid.