If there is one thing that every swimming pool must have, it is a pool filter. Swimming pool filters are the main process that keeps your pool clear from all the debris that can be brought in by rain, wind, toys, swimmers, and cleaning supplies. A swimming pool filter works to promote health and safety in the water. There are three main components in the filter that allows it to keep the water clear as well as safe. During filtration, there is a pump and motor that work together to bring the water in and push it out.