Sea-Klear Algae Prevention & Remover kills and prevents blue-green, black and mustard algae growth in a single treatment. Will not foam or stain but keeps water sparkling clear. One quart treats 20,000 gallons of pool water and will last up to three months. Sea-Klear Algae Prevention & Remover is odor-free and non-irritating, will not bleach hair or clothing, and is not affected by sunlight. Sea-Klear works well in all seasons, is an excellent winterizer and vacation treatment, and is ideal for Spring start-up. Algae Prevention & Remover reduces overall pool chemical costs.