We remain fully operational. Our teams are working around the clock to ensure your deliveries continue safely.
DOWNLOAD THE APP
Customer Services
Copyright © 2025 Desertcart Holdings Limited
DOWNLOAD THE APP
🌊 Clear water, zero worries — dominate your pond’s ecosystem with KnockDown Defense!
Airmax Knockdown Defense is a potent 2-in-1 liquid algaecide and aquatic weed treatment designed for ponds, lakes, and slow-moving waters. Its fast-acting formula eliminates a wide range of invasive aquatic plants and algae within 3-5 days. The easy-to-use liquid form allows precise dosing, making it ideal for professional and enthusiast pond management. With broad-spectrum efficacy and long-lasting results, it restores crystal-clear water and healthy aquatic environments efficiently.
| ASIN | B0B3Y5Z1S8 |
| ASIN | B0B3Y5Z1S8 |
| Best Sellers Rank | #21,333 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #73 in Water Garden & Pond Treatment |
| Brand Name | Airmax |
| Customer Reviews | 4.1 4.1 out of 5 stars (220) |
| Date First Available | June 13, 2022 |
| Item Form | Liquid |
| Liquid Volume | 16 Fluid Ounces |
| Manufacturer | Airmax, Inc. |
| Manufacturer | Airmax, Inc. |
| Product Dimensions | 5 x 2 x 9 inches; 1.43 Pounds |
| Target Species | Aquatic Plants |
| UPC | 810089840295 |
| Unit Count | 16.0 Fluid Ounces |
G**T
Aquatic weed killer and algae
This is really good stuff, but definitely do not make it too strong. It will even kill grass around. The pond if made to strong a bit pricey though
K**C
Pond algae and weed killer
Works great on algae and weeds.
T**E
IT WORKS!
I am not an expert on plants or weeds that invade ponds. I am an expert on knowing products that work! This product works! My pond was literally taken over by one invader that was not welcome! My pond is about an acre and is stocked with fish so I had to be careful. The weeds started dying in two days and there were no floating fish! BINGO!! The application is easy you simply walk around your pond and throw granules in your water!
S**E
Does not work. Save your money
It has been over a week and nothing is dying at all. I used 4x the recommended amount and nothing. Use copper sulfate! It is half the cost and kills everything in a few days. I only tried this because it was supposed to kill everything and last a few months. What a waste of time and money :(
B**.
Pond Water Clearifier
Makes the water pretty. Doesn't help with weed control.
A**R
Incredibly effective for duckweed. Killed all vegetation.
Absolutely blown away with how effective this product is. I used a single application as directed and it removed 100% of the duckweed in about 2 weeks. I planned a second treatment, but patience was all that was needed. Incredible product, wish I found it sooner. Also this pond is used for irrigation of the lawn and beds. I waited 5 days as per instructions before using for irrigation and had not issues with my lawn or plants. After pic shown first.
P**N
Only worked on a few lily pads.
I was highly disappointed in the quality of the product it performed very poorly and only killed a few of lilypads-the coloring changes on a few others, but didn't kill it. Not great for algae control. I like the opening, it was easy to use, I used a red solo cup to spread it. But the product was very expensive with very little results. I will be using diquat instead for the next time. Our pond bank is filled with nasty stuff and I was really hoping this would kill it, but it didn't.
A**R
Best pond product!
Why did you pick this product vs others?: I have had a pond for the last 12 years! Best product out there! 90 degrees and pond looks great!! I have spent so much money over the years. This is not cheap but at least it works!
Trustpilot
2 months ago
2 weeks ago