Hi all, I have a small pond that I created by hand about 5 or 6 years ago. It's small, about 2 by 4 foot, if that. Perhaps a foot and a half deep. In the first year I put some tadpoles in, and now every year, with virtually zero maintenance, the frogs and toads and newts spawn naturally which is fab as I know the pond can't be doing that badly. However there is alway loads of duckweed floating about, covering pretty much the entire surface area. Do I need to get rid of these every now and then? I really want to expand the pond but don't know how without ruining it.