How do swimming pools filter the water?

If the filter becomes clogged and it doesn't matter what type of filter the water that makes it through filtration is reduced and the amount of impurity's in the pool will increase this will lead to increased need of Chlorine or other sterilizer cloudy water as well as being a strain on the pump. If this is a salt water pool it will also lead to a shortage of chlorine. To maintain a pool properly and as economically as possible filters need to be kept clean.