sand in pool after backflush?

[wfbrad]

Hi guys, I have a 22000 gal in ground plaster pool. Swimquip sand filter, unsure of size, the decal is faded out from Arizona sun. Lately I have noticed that when I finish backflushing the filter, sand is coming out of the jets, about 1/2 cup under each on the 2 closest to the filter. What would make this happen? I changed the sand out last spring, but the problem did not show up until mid winter....

[Waterworks]

Normally if you have sand going back to the pool after a backwash it means that you are not rinsing, or your aren't backwashing for long enough. You should always backwash until the water comes out clear and then rinse for 30 - 60 seconds.

Brad
Waterworks Pools

[aylad]

Hi guys, I have a 22000 gal in ground plaster pool. Swimquip sand filter, unsure of size, the decal is faded out from Arizona sun. Lately I have noticed that when I finish backflushing the filter, sand is coming out of the jets, about 1/2 cup under each on the 2 closest to the filter. What would make this happen? I changed the sand out last spring, but the problem did not show up until mid winter....

It also can happen if you have a broken lateral in your filter, but the only way to check that would be to take the filter apart and remove the sand to look.

Janet

[Waterworks]

Normally, if you have a broken lateral, sand will go to the pool continuously, not just after a backwash. The fact that it only happens after a backwash makes me think you're not rinsing properly.

Brad

[DavidD]

I just bought a house with a Hayward Sand filter (model SP711 I Believe). After backwashing/Draining this weekend I noticed the same thing, Sand in the pool and on the driveway after backwashing. I did however go through the rinse cycle for a minute or two. Should you normally "Rinse" longer? I'm going to search for an owners manual online now but any advice on a sand filter would be greatly appreciated as I've only had D.E. filters in the past. I will say that I love having the ability to backwash and pump out a lot of water without having to replace the D.E.

Dave

[matt4x4]

Sometimes it's a sign of too much sand in tee filter too, however, you should NOT get sand into the pool after rinsing if levels are correct.
most lateral issues appear after winter since the filter tends to go through many freeze thaw cycles while sitting out there and any moisture left in there causes expansion and contraction, after numerous years of use, the plastic that the laterals are made from becomes more brittle and thus more susceptible to breaking. Anything over 4 years, I'd guess a lateral went south. Cheap to replace.