Our pool installer set our timer on our Pentair 1 HP whisperflo one speed pump to run 9 hours on, 3 hours off, 9 hours on, 3 hours off, in a 24 hour period. The pool is 25,000 gallons. He said it should turn the water over twice a day. After researching this site, it seems excessive to run it that much and my electrical bill has been high all summer long even though we've had to run our AC much less than previous years. How do I know how long it should run? I have found all sorts of calculations but they talk about pipe size and head and all sorts of things I don't understand. Anyone have a rough estimate? We have no water features. We use the BBB method.