Aquathol K Aquatic Herbicide jug (2.5 gal)

Aquathol® K is a professional aquatic herbicide formulated with 40.3% dipotassium salt of endothall for rapid control of submerged aquatic weeds in lakes, ponds, reservoirs, canals, irrigation systems, and other managed aquatic sites. Delivering 4.23 lbs. of dipotassium endothall per gallon and 28.6% endothall acid equivalent, Aquathol K provides fast contact activity against many troublesome aquatic weeds while dissipating quickly in treated water. Unlike many aquatic herbicides that lose effectiveness in muddy or organic-rich water, Aquathol K remains highly effective in turbid water conditions and areas with significant organic debris. Its contact mode of action makes it especially useful where rapid knockdown and shorter exposure periods are desirable, including flowing-water and canal applications. Aquathol K has become one of the most widely used aquatic herbicides for hydrilla, pondweed, milfoil, coontail, naiad, and other submerged aquatic weeds. Aquathol K may be applied as a surface spray, subsurface injection, drip application, or metered treatment depending on the target weed and waterbody characteristics.

Features & Benefits

✓ Contains 40.3% dipotassium salt of endothall for professional aquatic weed control

✓ Delivers 4.23 lbs. dipotassium endothall per gallon

✓ Controls hydrilla, pondweed, milfoil, coontail, naiad, and other submerged weeds

✓ Rapid contact activity with minimal long-term residue

✓ Performs well in turbid water and high organic matter environments

✓ Flexible application through surface spray, injection, drip, or metering systems

✓ Excellent choice for lakes, ponds, reservoirs, canals, and irrigation systems

✓ Effective in both quiescent and flowing-water applications

Labeled Use Sites

Lakes, ponds, reservoirs, canals, irrigation canals, drainage systems, flowing water, slow-moving water, quiescent water bodies, and managed aquatic vegetation sites. Not for use in brackish or saltwater.

Target Weeds

Hydrilla, curlyleaf pondweed, American pondweed, largeleaf pondweed, Illinois pondweed, floating-leaf pondweed, narrowleaf pondweed, threadleaf pondweed, variable leaf pondweed, coontail, horned pondweed, sago pondweed, milfoil, parrotfeather, naiad, water stargrass, and hygrophila (suppression).

Application Notes

Aquathol K is a contact herbicide and should be applied when target weeds are actively growing. For best performance, maintain adequate exposure time between the herbicide and target vegetation. Use lower rates for large treatment blocks where dilution is limited and higher rates for shoreline treatments, canals, boat lanes, or areas with rapid dilution potential. Because treatment of dense aquatic vegetation can reduce dissolved oxygen, heavily infested water bodies should be treated in sections to minimize stress on fish populations.

Why Choose Aquathol K?

Aquathol K remains one of the industry's most trusted aquatic herbicides because of its rapid activity, flexible application methods, and strong performance in difficult water conditions. Whether managing hydrilla in reservoirs, pondweed in lakes, or vegetation in irrigation systems, Aquathol K delivers reliable aquatic weed control while minimizing long-term water use restrictions.

Product Information

Active Ingredient: Dipotassium Salt of Endothall 40.3%
Endothall Acid Equivalent: 28.6%
Endothall Per Gallon: 4.23 lbs. Dipotassium Endothall per gallon
HRAC Group: Group 31 Herbicide
Formulation: Liquid Aquatic Herbicide
EPA Reg. No.: 70506-176
Manufacturer: United Phosphorus, Inc. (UPL)

• Concentrated aquatic herbicide for submerged weed control
• Controls hydrilla, curly-leaf pondweed, and other submerged weeds
• Fast-acting contact activity with short exposure time
• Minimal residual and rapid dissipation in treated water
• Effective in turbid water and high organic matter conditions
• Professional-grade liquid concentrate formulation

ACTIVE INGREDIENT	40.3% Dipotassium salt of endothall
TARGET PESTS	American Pondweed, Coontail, Curly Leaf Pondweed, Eurasian Watermilfoil, Hydrilla/Elodea, Parrot Feather, Sago Pondweed, Southern Naiad
FOR USE IN	Ponds, Lakes, Canals, Reservoirs
APPLICATION	The rate of application ranges from 0.45 – 3.2 gallons of Aquathol K per acre foot of water.
MANUFACTURER	United Phosphorus
EPA REGISTRATION	70506-176
NOT FOR SALE TO	AK, CA, CT, DE, HI, ME, MD, MA, NH, NJ, NY, OR, RI, VT, WA (Restricted to licensed applicators only)
COMPARABLE PRODUCTS	Amphithal

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