What is the base pressure for a filter on pool?

The base pressure of a pool filter is the initial pressure reading when the filter is first turned on and before any water has passed through it. Pool filters, like sand, cartridge and DE, are designed to remove dirt and debris from pool water. As the water flows through the filter, the pressure of the water increases. This is because the dirt and debris collect on the filter media, which restricts the flow of water. The base pressure of the filter is the pressure reading taken before any dirt and debris has had a chance to collect, so it serves as a reference point to determine the amount of pressure increase and the need for backwashing or cleaning.