Good questions! Labor is not an issue - but manual removal is not an option, I tried!
I'm in the st louis area, pond is about 2 acres. 30% is less than 3' the rest 4' - 8" approximately.
I would like to treat chemically. I will be taking ph levels this weekend, and may begin a fertilization program in the spring - too late now due to the weed issue.
The water is very clear, partially filled by well water. No filtration / areator. Hope that helps some!