slider, the biggest asset to the overflow box is the fact that it holds a syphon without drawing water because of its construction. What happens if your power trips for a couple minutes, the syphon tube draws that inch of water and breaks syphon, now the power starts up again and your pump starts returning water to the Display Tank, now you have no draw out of the tank and you are adding water. You will overflow your Display and also burn up the pump when the fuge/sump dries out. Its much more safe to go about it in the "best option available" rather than taking a short cut and getting burned in the long run.