Your pool's filter is what keeps the water clear, catching dirt, oils, and debris before they build up in the water. Over time, cartridge and DE (diatomaceous earth) filters fill with what they've caught, which restricts water flow, strains the pump, and lets cloudy water and algae take hold. A clogged filter also forces your equipment to work harder, which can shorten its life and raise your energy costs. Regular cleaning keeps water moving freely and helps your chemicals do their job. Cartridge filters need to be removed and thoroughly cleaned, and worn cartridges replaced. DE filters need to be cleaned and recharged with fresh DE so they filter properly. A professional knows how often each type needs attention and can spot wear early, so your pool stays clear and your equipment lasts longer.