Aquathol K Liquid Herbicide is effective against a broad range of aquatic plants with a wide margin of safety to fish and other aquatic life. Aquathol K may be used in quiescent or slow moving waters and flowing water systems. Do not apply before weeds are present. For best results, water temperature should be 50 degrees Fahrenheit or higher. Aquathol K treated water may be used for swimming, fishing, livestock watering and irrigating turf, ornamental plants, and crops with a few exceptions (please refer to the label). Application rates range from 0.45 to 3.2 gal per acre foot of water treated. Aquathol K Liquid Herbicide works especially well for early season curlyleaf pondweed, and should ideally be applied when water temps are between 55-60 degrees Fahrenheit to target young curlyleaf plants. Make sure to check local permitting requirements when applying this product, and always adhere to label guidelines for proper dosing.