I have a 1/4 acre pond in Southeast Michigan. It is stocked with largemouth bass and hybrid sunfish. This year, our pond has been overrun with Bushy Pondweed. I have read about some chemicals to control this type of weed, such as Hydrothol 191, but I am concerned about fish kills. Any recommendations for a solution to getting rid of the Bushy Pondweed without affecting the fish?