Right now our ducks are using a plastic kiddie pool, but we're having some problems. It's so large that I can't clean it easily so it's constantly green, and our bright sun is really hard on the plastic. We have pond liner left over from another project, but it seems like an in-ground pond would be even harder to clean, and some of our ducks are muscovies with long claws on their feet. Money is also an issue, so just purchasing a rubber or metal tank is out. Any ideas?