Pool filter sand's lifespan is rather short, if you keep up maintenance (backwash your sand filter every 3-5 weeks and deep clean it 2-4 times per year), your pool filter sand should last you up to 5 years.

      Does that mean changing the sand more often is a good choice?

      The strict answer is no. There’s a sweet spot for how old your sand should be. Pool sand is most effective after about 2 years of use because for the first couple of years the contaminants building up also act as filtration for the water that passes through the filter.

      But eventually, gunked-up sand doesn't filter properly, all gunk builds up  and the filter tank to clog up.

      Here are some signs you need to replace the sand include: pressure buildup (once the pressure reads above 10 psi), channeling (open up the pool filter and check for ridges in the sand or gaps where water could easily make its way through), and cloudy water.