backwashing
/ˈbækˌwɑʃɪŋ/
noun
- The process of cleaning a filter by reversing the flow of water through it, especially in pools, aquariums, or water treatment systems.
- The pool maintenance schedule includes backwashing the filter every two weeks.
- Backwashing removes trapped dirt and debris from the sand filter.
- You should perform backwashing when the pressure gauge shows a rise of 8–10 psi.