No residual weed control. Effective in burning off Duckweed and Watermeal Mats add non-ionic surfactant to enhance kill.
Can be mixed with AquaVet Algae control for synergistic control of submerged aquatic weeds (see label rates). 1 quart with 25 gallons water plus 8 oz of Surfactant treats 10,000 sq. ft. surface area. Treat clear calm water (avoid turbid, muddy water).