Filter pressure keeps spiking randomly.

[Isabella]

I’m stumped here, my sand filter pressure will be normal around 15 psi, then out of nowhere it jumps up to 30 psi within a few hours even if the pool doesn’t look dirty. Backwashing brings it back down, but the cycle repeats almost daily. Never had this issue in past seasons. Any idea what could be clogging it so quickly?

 

[Freddie]

I’m stumped here, my sand filter pressure will be normal around 15 psi, then out of nowhere it jumps up to 30 psi within a few hours even if the pool doesn’t look dirty. Backwashing brings it back down, but the cycle repeats almost daily. Never had this issue in past seasons. Any idea what could be clogging it so quickly?

That’s unusual if the water is clear. Sometimes fine debris like pollen or even dead algae can clog up the sand faster than you’d expect. Could also be channelling in the sand bed, have you replaced the sand in recent years?

 

[Isabella]

That’s unusual if the water is clear. Sometimes fine debris like pollen or even dead algae can clog up the sand faster than you’d expect. Could also be channelling in the sand bed, have you replaced the sand in recent years?

Yes

 

[Zephyr]

I’m stumped here, my sand filter pressure will be normal around 15 psi, then out of nowhere it jumps up to 30 psi within a few hours even if the pool doesn’t look dirty. Backwashing brings it back down, but the cycle repeats almost daily. Never had this issue in past seasons. Any idea what could be clogging it so quickly?

I’ve had that happen before when I had a hidden algae problem. Water looked fine but the filter was catching microscopic stuff constantly. A good deep clean of the sand and maybe adding a little DE powder to help polish might give you some answers.

 

[Lily Allen]

I’ve had a similar issue with hidden algae. The water seemed fine, but the filter kept catching microscopic particles. Did a deep clean of the sand and added some DE powder. That helped a lot in smoothing things out. Anyone else use DE powder to fix random pressure spikes?

 

[Mariam Agyeman]

I’ve had that happen before when I had a hidden algae problem. Water looked fine, but the filter was catching microscopic stuff constantly. A good deep clean of the sand and maybe adding a little DE powder to help polish might give you some answers.

 

[Oscar Ricci]

What caught me off guard once was that it wasn’t obvious debris but a thin biofilm layer inside the sand bed. The water looked clear and chlorine was stable, yet pressure spiked quickly because the sand pores were coated with fine organic buildup. In my case, after a thorough deep clean until the backwash water ran completely clear and checking phosphate levels, the 15 to 30 PSI jump stopped. Sometimes the clogging isn’t visible in the water, it’s building up inside the media.