Yes, running a pool pump does add to your total monthly electric bill however, it must be done. But just how many hours a day you run your pump will help you keep your cost at a minimum.
State codes for public pools are “4 turnovers” per day. A turnover is when all the water in your pool passes through the filter.
For example: A 10,000 gal pool with a standard pump will pump approximately: 60 gallons per min/3600 gal per hour/1 turnover per 3 hours. Therefore, the run time for this pool needs be 12 hours to meet state code.
There is no such code for private pools, but here is a rule of thumb you should follow. Run your pump for 1 hour per day for each degree of the average high temperature for the day. So, if at 3:00 PM the temperature was 90˚, then you should be running your pump 9 hours per day.
Here are a few additional thoughts that you should factor in:
The pool pump uses the most energy turning on, so once it is on it doesn’t cost much to run. Environmental factors and bather load effect the time you should run your pump. Talk to your service tech to help determine your pools specific needs.