SePRO Sonar A.S. Aquatic Herbicide


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

  • Season Long Weed Control
  • Treats Floating & Submerged Weeds
  • Systemic Herbicide That Kills Roots

Even the most persistent weeds don't stand a chance against Sonar™ herbicide. SePRO Sonar™ A.S. Aquatic Herbicide can be used to control stubborn aquatic weeds in fresh water farm ponds and lakes. Treating your pond with SePRO Sonar™ A.S. Aquatic Herbicide early in the spring provides season-long control against undesirable aquatic vegetation. Sonar™ A.S. is ideal for waterbodies with minimal water outflow. 8 ounces of Sonar™ A.S. herbicide for ponds treats 1/4 acres 4-6 feet deep.

SePRO Sonar™ A.S.

Tech Specs

Usage Information

SePRO Sonar Aquatic Herbicide 8 Ounce
8 Ounce
SePRO Sonar Aquatic Herbicide 16 Ounce
16 Ounce
SePRO Sonar Aquatic Herbicide 32 Ounce
32 Ounce
SePRO Sonar Aquatic Herbicide 1 Gallon
1 Gallon
Application Liquid Liquid Liquid Liquid
Temperature Restriction None None None None
Pond Size Treated (4-6 Feet Deep) Up to 10,000 Sq Ft Up to 20,000 Sq Ft Up to 40,000 Sq Ft Up to 160,000 Sq Ft
Shelf Life 2 Years 2 Years 2 Years 2 Years

Dosage Rates

Treatment Area (Square Feet)
Sonar™A.S. (Ounces)
Water (Gallons)
10,000 Sq Ft 8 oz 2 Gallons
20,000 Sq Ft 16 oz 4 Gallons
40,000 Sq Ft 32 oz 8 Gallons

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

How To Apply

Mix the amount of Sonar™A.S. and water in a tank sprayer according to label instructions. Do not spray directly onto floating weeds and algae. Place the spray tip beneath the water's surface and apply beneath the water's surface. Over time, the weeds will begin to brown and die. Once completely dead, use a rake, like the Pond & Beach Rake, to remove dead weeds to prevent an accumulation of dead plant material and muck.

When To Apply

Sonar™A.S. has no temperature restriction, but it should be applied in early spring, at the first sign of weed growth. It can take 30-60 days to control established weed growth and up to 90 days for full protection of your pond. We recommend using pond dye to reduce sunlight exposure that can reduce treatment effectiveness.


  • Wait 30 days before using treated water for irrigation.


Replacement Parts

Here are the replacement parts for SePRO Sonar ™ A.S. Aquatic Herbicide.

Weeds Treated

The first step towards effectively treating any pond weed is proper identification. SePRO Sonar A.S. Aquatic Herbicide is recommended for use against each of the weeds listed below. Click on your desired weed for more information and alternate control options.

  • American Pondweed
  • Bladderwort
  • Coontail
  • Curly Leaf Pondweed
  • Duckweed
  • Eurasian Watermilfoil
  • Hydrilla/Elodea
  • Sago Pondweed
  • Southern Naiad