Gentle hose and mild cleaner are all you need.

Gentle hose and mild cleaner are all you need.

Yes. Use a garden hose with a gentle spray nozzle, not a pressure washer. Soak grids in a mild filter cleaner or dish soap solution, then rinse thoroughly. Scrubbing is for stubborn spots only — and use a soft brush.

The biggest mistake people make is cranking up the pressure. A pressure washer will fold the pleats, tear the fabric, or warp the frames. You don’t need high pressure — the dirt comes off with soaking and moderate flow. If algae or oils are baked on, use a dedicated cartridge cleaner (they’re pH-stable for the grid material) rather than bleach or muriatic acid. Those weaken the polyester fibers over time.

Let the grids air dry completely before reinstalling. Wrinkled or deformed grids are a sign you’re being too aggressive. Replace them when the pleats crack or the end caps loosen.

Better to take an extra ten minutes than buy new grids.