As said above, for a fowlr you won't need a skimmer if you keep up with your water changes! I would recommend getting an aquaclear filter and find one of the surface skimmer attachments for it. That's exactly how I have my 50g fowlr setup and it works well. It goes against everything I do with my full blown reef tank, but it's nice to have a simpler system for the fish! With some t5 or LED lighting, you could keep zoanthids and some other softies in there as well. You'll get hooked!