Kelly you are right on ther money, In the summer without rain the elodea and duckweed, mostly the elodea gets thick rain when it doesn't rain and the water drops, but them is completely gone for 2 to 3 days after the rain, then grows back. How do you get rid of elodea manually, that might make for a really good part of my project. By the way thanks for the drawings and pics, I'm going to use themin my project presentation. I do wamt to keep some of it for the bass to get up under, but I would really want the elodea on the shallow flats to be gone, I don't mind it in the deeper water so much. By the way, how do I do a bathymentric assesment? Who should i talk too? I want to, if possible scatter the structure throughout the shallow and deep parts of the pond if appropriate.