i HAD some pondweed around the edges, out maybe 5-10 ft from the shore. several hunderd linear ft around the shore. i sprayed with diquat and in less than 24 hours it was DEAD and so was some weedy grass growing around the ponds edge. i dont mean kinda brown, i mean dead. i have never seen anything act so fast. i added a little cutrine as advised in an earlier post. i had a little fa which i always keep a little cutrine around for.. i also have chara, even the submerged plants look brown.

i added about 1 ounce or less of diquat per gallon of water. i made up 7 gallons.. i added one small gulp of cutrine.

it worked great, just make sure it only hits what you want dead.

Scott, I'm having my first serious problem with blue/green algea and Chara. How does the mixture get down to the the Chara submerged to 3' or even deeper? Do you know the brand names of any other Chelated copper algicide?

You could just sprinkle in copper sulfate crystals to reach the bottom correct?

bob-o, i had a little cutrine mixed with the diquat. the cutrine makes the mix really blue. i could see the blue coloring going down toward the plant by just spraying it on the surface. i had used the cutrine granules before and it didnt seem to work. I am keeping my fingers crossed.

Thanks Scott.