Pond Logic<sup>®</sup> Algae Defense<sup>®</sup>

Pond Logic® Algae Defense®

Algae Control

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Rated 4.3 out of 5, based on 4 reviews

Cannot be shipped to AK, CA, CT, DC, HI, ME, NJ, NY, PR, RI, WA or Canada

  • 530130 - 1 Gallon
  • $39.99
  • 4+ $34.99 Each - Gallons
  • 530332 - 1 Gallon w/ Treatment Booster™ PLUS
  • $49.99
  • Eliminate Algae Quickly
  • Fast Acting Liquid Formula
  • Spray Directly Onto Algae Blooms

Eliminate algae blooms and green water from your pond with Pond Logic® Algae Defense®. A fast-acting liquid formula, Algae Defense® can be directly applied via a pressurized sprayer to combat floating filamentous algae, chara or the planktonic algae that causes green water. Each gallon of Algae Defense® treats up to 8,000 square feet and can be used when water temperatures are at or above 60°F.

Pond Logic® Algae Defense®

Tech Specs

Usage Information

Pond Logic Algae Defense
1 Gallon
Application Liquid
Temperature Restriction Use When Above 60°F
Square Footage Per Gallon Up to 8,000 Square Feet
Shelf Life 2 Years

Dosage Rates

Treatment Area
Algae Defense®
Treatment Booster™ PLUS
1,000 Square Feet 1/2 Quart (16 Ounces) 1-1/4 Gallons 4 Ounces
2,000 Square Feet 1 Quart (32 Ounces) 2-1/2 Gallons 6 Ounces
4,000 Square Feet 2 Quarts (64 Ounces) 5 Gallons 12 Ounces
8,000 Square Feet 4 Quarts (1 Gallon) 10 Gallons 22 Ounces

Please note: Above are recommendations. Always read the product label.

How To Apply Algae Defense®

Mix the amount of Algae Defense® and Treatment Booster™ PLUS (if using) with pond water in a tank sprayer according to label instructions. Use a pressurized pond sprayer to spray the Algae Defense® mixture directly onto to the target algae. Treat only up to half of the pond's surface and wait 10-14 days before a second treatment. In hot weather or when fish are stressed, treat only 1/4 - 1/3 of the pond's surface at a time. Over time, the algae will begin to brown and die. Once it is completely dead, use a rake, like the Pond & Beach Rake, to remove dead algae away to prevent an accumulation of dead algae and muck.

When To Apply Algae Defense®

Algae Defense® should be applied when algae is actively growing. Begin applications when algae first appears. Unless steps are taken to reduce the overall nutrients in the pond, multiple applications may be needed for full season algae control. Use with Treatment Booster™ PLUS for best results.


  • Do not use in ponds with koi, grass carp or goldfish. Not for use in water garden or koi ponds.
  • Do not use in ponds with trout, unless carbonate hardness is above 50ppm.


Replacement Parts

Here are the replacement parts for Pond Logic ® Algae Defense ® .

Weeds Treated

The first step towards effectively treating any pond weed is proper identification. Pond Logic® Algae Defense® is recommended for use against each of the weeds listed below. Click on your desired weed for more information and alternate control options.

  • Chara
  • Filamentous Algae
  • Planktonic Algae
  • Pond Logic(r) Algae Defense(r) Algae Control Pond Logic® Algae Defense® - Algae Control

    Learn how to apply Algae Defense®

  • Pond Logic(r) Treatment Booster(tm) PLUS Surfactant Pond Logic® Treatment Booster™ PLUS

    Learn about the benefits and how to mix Pond Logic® Treatment Booster™ PLUS in this product video.

  • The Airmax(r) Ecosystem(tm) Video The Airmax® Ecosystem™

    Learn about the revolutionary proactive pond management approach. By understanding your pond's life cycle, and with the help of Airmax® Aeration, Natural Bacteria and Pond Dye, you can learn just how easy pond management can be.

Write a review
Jul 17, 2010 | By Robert Smitth
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for the price its a good item, didnt like spraying under the water, but killed my alergy quick

Jul 27, 2010 | By Kay Foutz
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As suggested...I used with the surfactant and how AMAZING the products are. Fast acting too. Got rid of the green icky stuff and now the water is so clear and inviting.

Aug 2, 2011 | By Felix Felde
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We used Algae Defense with Cide Kick on our pond, and after two applications, the algae is only slightly improved. Unfortunately, we learned that hard way that this stuff kills frogs and tadpoles. ALL of them.

Very amazing
May 31, 2012 | By Tom Irish
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I used this product on our pond and this is the first time in 25 years that someone has swam in the pond. All the kids say thank you Pond Guy. Also the pond dye is a great product!!

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