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CrystalClear® AlgaeOff™

Regular price $23.50 USD
Regular price Sale price $23.50 USD
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CrystalClear AlgaeOff utilizes the latest in oxygen technology to remove string algae quickly and efficiently. CrystaClear AlgaeOff is an EPA registered granular algaecide that works on contact. Kills and removes algae on rocks, streams and waterfalls.

  • Kills & Removes Algae
  • Fast Acting and Works On Contact
  • No More Algae
  • Will Not Harm Fish or Ornamental Plants***
  • Great For Rocks, Streams & Waterfalls

*** When Dosed As Stated On Label

AlgaeOff 2.5lbs:

Treats up to 1,000 sq. ft.
Has a shelf life of 5 years


25-50 sq. ft.        1/4 cup
51-100 sq. ft.      1/2 cup
101-150 sq. ft.    3/4 cup
151-200 sq. ft.    1 cup
201-250 sq. ft.    1-1/2 cup

Please note: Above are recommendations for light algae growth. Dosage rates may double with heavier growth. Always read the product label.

When to Use

AlgaeOff can be used as needed to kill or remove actively growing algae at the prescribed rate to treat existing algae growth. AlgaeOff is ideal for rocks, streams and waterfalls.

How to Apply

AlgaeOff is water activated. Apply AlgaeOff granules over a wet surface that has algae growth or activate with water immediately following application. For waterfall applications, turn off waterfall pumps and allow AlgaeOff to sit on the waterfall for a period of 20 minutes and then turn pumps back on.

Skim the dead algae or organic material that rises to the water’s surface after treatment. This will keep dead organics from sinking to the bottom of the pond. Dead and decaying organics provide a food source and additional nutrients for future algae blooms. Allow 48 hours between consecutive treatments.

For liquid applications, please follow all label instructions. Due to solubility, AlgaeOff is not as effective with this application method.



After application, do not allow undiluted granules to remain in an unsupervised area where humans or animals are exposed.

Be careful when applying granules. Non-targeted plants will suffer contact burn if undiluted granules are accidentally spilled on them.

AlgaeOff cannot be shipped to Alaska, Connecticut, Hawaii, Puerto Rico or Canada.


Product Notices:

Keep product away from children and pets when not in use. AlgaeOff becomes hazards to humans and domestic animals – if absorbed through the skin or swallowed.