Is your above ground pool pump costing alot in hydro? It may be worth considering a new 2 speed pump. Having a low speed setting allows the pool to filter on low speed, saving over 60% in hydro costs. Rather than timing the pump on and off, you can filter on low all the time, when vacuuming, back washing or adding chemicals....simply turn it on to high speed for a day or so. Not only will you save in hydro cost, it will lessen the possibility of the pool going green which often happens when timing the pump on and off.