3 month algae control. 16 oz (ounces) treats 10,000 gallons of pool water every 3 months to prevent algae growth. Add 32 oz per 10,000 gallons for severe algae growth. Reduces overall pool chemical treatment cost by killing existing algae growth and preventing future outbreaks. Non-staining, odor free, and non-irritating. Ideal for spring start-up, season end closing, and when leaving on vacation to ensure a clean pool.