How a pool works is not as complex as people think. It is a self-contained body of water, no fresh water supply is needed except for periodic refilling from splash out or evaporation. The water is pulled thru a dual bottom main drain and top water skimmer from a pump that runs 24 hours per day. It is most common and efficient with a variable speed or 2-speed pump for overnight periods to conserve energy. Then water is pushed through a filter to clean dirt and debris. The next phase is the optional heater which is definitely recommended in Indiana for extended season life. Finally, there is the process of disinfection of bacteria. We prefer the saltwater process as opposed to straight chlorine. This process called “turnover” happens multiple times in a 24-hour period to keep the pool clean and disinfected.