Thanks for the in-depth response Bill. I've attached a picture with coontail. Yes, it is big rafts of plants that aren't attached to the bottom. We sent water in for testing, and I'd attach the pdf report, but I'm not sure how to do it. The test didn't show any major nutrient issues, yet clearly we have them based on the amount of plant life we have. I'm thinking that the aeration and maybe grass carp and catfish are stirring up the muck layer and consistently providing nutrients to the extensive plant life. I feel this way because we've had a drought the last 2 years, so other than a couple of flooding instances this summer, no additional nutrients have been introduced from the watershed.
In an ideal world, we'd have the money to drain, dig out the muck, and start all over again, but in my world I doubt I can afford that. We did not talk to Bruce Kania, but we've been working with the distributor for our area, Martin Ecosystems. Our hope is that the plants in the island will out-complete the other plants for nutrients. That is also why we're considering a few more islands. I think the islands, manual harvesting, selective herbicides for duckweed and water meal, and aeration are about the best I can do now with the funding constraints I have.
I agree, there are no magic bullets or guarantees, but I think the plan of action I'm considering will get me back to balance in the next few years. Please let me know if I'm missing something other than draining and starting all over again. Also, let me know if you're interested in seeing the lab report; I could forward it to your email. Thanks again for the great response.
