Pool Filter Cleaning

Manufacturers set a minimum of twice a year for cartridge and DE filters, and that is the number to treat as a floor. In practice the interval depends on filter type, pool size and what the pool is catching — a Hill Country pool under cedar canopy in February loads a filter far faster than the same pool in September. The pressure gauge is the real guide: a rise of 8-10 psi over the clean baseline means it is time.

No, and the difference matters. Backwashing reverses flow to flush loose debris, which helps a sand or DE filter between services but never removes the oils and fine particulate bound into the media. A cartridge filter cannot be backwashed at all. A proper clean means opening the tank and washing the elements individually.

Pressure climbs, flow drops, and the pump runs against resistance it was not sized for — which shortens motor life and starves the heater and salt cell of the flow they need. Circulation is also what makes chlorine work, so a blinded filter shows up as water that will not hold a residual no matter how much you dose it.

Cartridges have a finite life — the pleats lose structure, the fabric stops sealing, and pressure returns to high quickly after a clean. DE grids tear. When we open the tank we tell you which of those you are looking at, because cleaning worn media is money spent to arrive back where you started in a fortnight.

Yes. It is part of the rhythm of weekly service for our regular accounts, and we also do it as a one-off for pools we do not otherwise maintain — including before an inspection or a property sale, where a clean filter and a recorded baseline pressure make the equipment report considerably easier to read.