Works on contact to immediately remove string algae. AlgaeOff® is best suited for pondless water features. It can be used when needed but is most effective when algae is actively growing.


Effects of AlgaeOff® treatment are immediately apparent (bubbling, bleaching/discoloration of algae).


  • Turn off water pumps and fountains before applying CrystalClear® AlgaeOff®. Apply granulars directly on to damp, infested areas. Let it set for 15-20 minutes before turning on pumps. Remove any debris after treatment and wait at least 48 hours if second treatment is required.


    Apply early in the day under calm, sunny conditions and when the water temperatures are warm. Sunlight and higher temperatures both enhance AlgaeOff®’s effectiveness.


    Length x Width x Average Depth x 7.5 = gallons

    Water Volume



    Approx. Volume

    100 1/2 tsp
    500 2.5 tsp
    1,000 5 tsp
    5,000 1/2 cup (4oz)