I have a pond about the same size as yours and had the same problem with duckweed, water meal, and coontail a couple years ago. I sprayed with Clipper and a surfactant twice that year. First time I sprayed it, it knocked out about 85% of it, second time was just to clean up the remaining. Thanks again to Esshup for the advice on mixing and application. Last year and so far this year my pond has been free of any of them. I am very impressed with the Clipper herbicide. The thing I like most, is that it doesn't take much and its a contact herbicide, so you don't have to worry about outflow of the pond like some of the chemicals. I wish I knew you were looking to buy some Clipper, I have two unopened one pound containers that I am looking to sell and will make someone a good deal on them, if interested pm me. When I bought the Clipper, I thought I was going to have to treat the whole body of water, not just surface treatment, so that's why I have the extra two pounds. I also did the ph test and sprayed early in the morning.
