The only negative to what I suggested is, you can't see when all the turds are gone. Maybe you could find a clear pipe and make it. Or cut a window in it and silicone a piece of plexi in. Also might want to put a valve in the hose to control flow if you use sand as a substrate. You can buy those pumps for filling waterbeds at hardware stores too. I don't use my pump, I just siphon out the door. If I am lucky, someday the dog will push the door and get away, but that is a whole other story.