What filtering is for

Filtration removes suspended dirt and distributes the products around the pool. Without enough filtration, even the best chlorine won't keep the water clear.

How many hours a day

Two practical rules — take the larger:

  • By volume: the water should pass through the filter ~2 times a day (volume ÷ flow × 2).
  • By temperature: filter as many hours as half the water temperature. At 28°C ≈ 14 h/day.

Spread the hours across the day and prioritize the sunny hours, when it gets dirtiest and consumes the most chlorine.

Backwashing a sand filter

When the gauge pressure rises ~0.3–0.5 bar above normal, it's time to backwash: reverse the flow to expel the dirt, then rinse and filter again.

Maintenance

  • Empty the baskets in the skimmer and pump every week.
  • Check seals and gland if you see leaks.
  • A cover at night reduces evaporation and chlorine loss.