If you've read one of my previous posts, you'll know that several of my big stocktank watergardens were totally covered with duckweed. My lilies weren't growing very well, so I was thinking there was too much duckweed. So I began removing some........maybe 1/4 at a time. Last I looked, there was still plenty of duckweed. Then, all of a sudden, over the course of just a couple days, there's no sign of it.........nothing, nada, zip!

I've had tadpoles in there all along, and they didn't seem to be eating it. Is it possible they grew up along with their appetites? Is it possible a few cold nights in the low 50's killed it off? Is it possible that the lily got the sun it needed and grew fast and is using up the good stuff in the water, and leaving nothing for the duckweed?
It's all very strange. Any explanations?
Thanks.