That would be an awesome thing to do on a smaller tank...I don't have the patience to wait for a ton of water to drain through airline tubing though LOL. I have a 8" piece of PVC pipe and a cap that I'm going to paint black, it should be sticking up just about an inch over the substrate and I'll hide it behind plants. I wonder...I need to put it through the quilt batting and fiberglas screen, can I cut a hole just big enough for it then hot glue the material around it so that it doesn't allow soil to go through around the pipe?