Backwashing question.

[JenLM]

How long to do you backwash your pool? My husband has been backwashing until the water looks clear (2-3 minutes), then rinsing and going back to filtering. The jets will then spit out dirty water for several minutes. Are we backwashing long enough. We have been working on clearing all of the algae out of the pool, but it now seems to be clearing up.

Thanks for all of the help. This forum has lifted a HUGE weight off of me as a new pool owner.

[AnnaK]

I backwash until the discharge water is clear. Instead of using the sight glass on the sand filter I catch some of the waste water in a white plastic pitcher during the process. It's easier for me to see whether it's clean that way. Then I rinse for at least 30 seconds. If I have enough water in the pool, like right now after some heavy rains, I do the backwash/rinse cycle twice. My experience has been that rinsing for a good 30 seconds and longer, if you have enough water in the pool, is critical.

Be sure you turn the pump off before you change the setting of the multiport valve handle.

If you get dirty water or sand blowing back into the pool you may not be rinsing long enough to pack the sand back down. Or you may have a bad spider gasket (easy to replace).

[CarlD]

I don't think you are doing anything wrong. I think AnnaK's alternatives two alternatives of the sand or spider gasket are far more likely.

I normally simply backwash by going to waste, then to backwash. I wait till the sight glass is running clear for 10 or 15 seconds, back to waste, and back to filter. You turn off the filter to reduce pressure on all the components in the multivalve but also in case you release the handle in the CLOSED position with the pump running the multivalve will probably be damaged.

I NEVER have any blow-back as you describe. I don't go through AnnaK's elaborate procedure (not that it's wrong, and it works for her pool) because by doing so my pressure drops back to "normal" (for my pool, 20psi is the norm when the pump is on high).
Carl