In The Swim Pool Algaecide 60 Plus - 2 x 1/2 Gallons 2 x 1/2 gallon bottle quantity Non-metallic, non-foaming, low-odor polymer-based algaecide Not affected by pH and recommended for us in well water Can be used in conjunction with a shock treatment Initial Dosage: 6-11 ounces per 10,000 gallons, Maintenance Dosage: 2-4 ounces per 10,000 gallons