I had a 30 foot round pool installed a little over 2 years ago. Last summer my liner caught several leaks due to nutgrass/nutsedge. Now, I'm having to replace the liner, but I need help choosing a protective barrier against the nutgrass nightmare. What has anyone heard or experienced with Perfect Pool Bottom, Supreme Hard Bottom, and Happy Bottom? I'm having a hard time choosing because I don't want to waste $2000 by purchasing a bad product. Thanks!