Durvet AquaVet Copper Sulfate is an algaecide and herbicide designed to control floating, submerged, and planktonic algae in ponds and lakes. Use 2.5–4 lbs of granules per acre, mixed with 10–15 gallons of water, dissolved completely and sprayed over algae mats. Treat no more than ¼ to ⅓ of the pond at a time to prevent oxygen depletion, waiting 7–10 days between applications. Early treatment is recommended, and re-treatment may be needed during the season. Safe for immediate water use, it helps control microscopic algae, filamentous algae, chara, and unpleasant odors, restoring pond health and clarity.