Leff from Safety Harbor,fl writes,
How many oz's of Diquat per gallon of water to kill Duck Weed in a pond
For duckweed control, apply Diquat Water Weed and Landscape Herbicide at 1-2 gallons per acre plus 32 oz per acre of surfactant in at least 100 gallons of water. Treatment of dense weed areas may result in oxygen loss from decomposition of dead weeds. This loss of oxygen may cause fish suffocation. Therefore, treat only 1/3 to ½ of the water body area at one time and wait 14
days between treatments. Please let us know if you have any other questions, or give us a call at 1-866-581-7378 since many times with these types of applications, a customer service representative can better explain application techniques over the phone.
Answer last updated on: 09/23/2014