What is it, what does it do and how do I use it? Part 2 of 7: Skimmer

Most residential swimming pools are equipped with a skimmer. These are boxlike openings in the wall of the swimming pool that allow water to enter the circulation system. There should be 1 skimmer for every 400-500 square feet of swimming pool area. Inside the skimmer we will find some sort of floating weir. In some pools it will be a circular contraption that moves up and down, where in most modern skimmers it will be a door. This weir adjusts to the level of the water in the pool and makes it flow faster into the skimmer so that more contamination enters the system for treatment. When the pumping system turns off, the weir rises to trap all the surface contamination in the skimmer. YES, it serves a purpose and needs to be there! Also found in the skimmer is a large mesh basket. This basket traps large particles and keeps them from entering the pump. It has to be in good shape (no breaks or missing chunks) as it prevents large debris from damaging the pump and impeller. In some pools, the main drain is plumbed to the second port in the skimmer so that if the basket gets filled, the pump wont starve for water. This practice is not recommended due to the possibility of suction entrapment (VGB Act)