I drained and revamped my 2.5 acre pond recently. It was finished and stocked two springs ago. As of that summer, coontail came back vigorously. I raked on it that summer. The next summer it came back worse. We also had a lot of spring algae mats those first two springs as it warmed up outside.

Here's what I have in my pond now and both the algae and coontail problems appear to be eliminated going into my 3rd spring.

I installed aeration during the first spring.
I stocked about 12 - 16 grass carp that were about 8-10" long.

It seemed like by late summer, or early fall of last year, the mass infestation of coontail disappeared. I had raked about half of it out that summer but there was no way I had the time or back to get all of it. Somehow, it disappeared and I am convinced the carp had grown enough by the second summer to have destroyed the stuff. Currently, from the looks of them swimming, I'd say they are at least five pounds and probably had grown large enough by the second summer to have eaten all of that.

The floating algae mats did not happen this spring either. I am not sure what is responsible. The neighboring ponds got it bad once the sun was out and warming everything but my pond was wonderfully clear of it. I don't know if my catfish, carp, aeration, muck away, or what it was that made the difference this third spring.

Anyway, the main point I wanted to make is that I believe my grass carp are the key factor in eliminating the coontail. That plant is a scourge and can take over a pond to the point of reducing most or all recreational fun. It did for us before our redo. We are so thrilled with how well our pond is doing now. It's beautiful and we get many positive comments from visitors. I love our aeration too, especially while we have guests over swimming. It's funny to float over them and feel that super cold bottom water bubbling up.