Sand in bottom of pool

sevver

Well-known member
Mar 27, 2007
477
Morris, IL
#1
I have had sand in the bottom of my pool for the last couple of years. I figured it had a broken slit in a lateral someplace and that it was not a big deal. Well, I just backwashed really good, after vacuuming really good the other day, and there is sand on the bottom again. I now am wondering, is it possible for the sand to be getting in after getting stirred up from backwashing? I did not have sand on the bottom for a while before I did that.
 

duraleigh

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Apr 1, 2007
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Sebring, Florida
#2
Hi, Steve,

Assuming you have a multi-port valve, I would say it is possible. I find if I don't put my multi-port in the "rinse" position for at least 45 seconds, I do get dirt back into the pool. Not much, but nevertheless some.

The innards of my filter and exactly how that water flows thru the filter and the valve are not as clear to me as it should be. The way I picture the insides, I see no way for the dirt (sand) to go back to the pool but it obviously does so I don't understand that device as well as I should.

In short, are you rinsing long enough?

Now, if you don't have a multi-port with a "rinse" position, disregard my entire post because I have never seen the insides of the slide valves that are on some filters.

This is one of those posts that's long on text and short on answers. I'm pretty much looking for answers myself rather than providing any.
 

JasonLion

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May 7, 2007
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Silver Spring, MD
#3
In some areas sand is blown into the pool from "outside". This will only happen in arid climates or if there are sand dunes nearby, so you should know right away if this is a possibility.

In normal operation sand should never come out of the filter. In some systems skipping rinse could cause problems, but that should be a rare exception, not something that happens ever time. 99% of the time sand in the pool means a cracked latteral.
 

sevver

Well-known member
Mar 27, 2007
477
Morris, IL
#4
I never rinse. Should I?! I put the vacuum on, vacuum, then shut off the pump, and backwash until the water is clear, and then some, then I put it back on filter.
 

duraleigh

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#5
Yeah, Steve, if you've got a "rinse" setting on your valve, you should use it after backwashing. Some say 15 seconds...I have to do it for 1 minute to get only clear water back to my pool.
 

sevver

Well-known member
Mar 27, 2007
477
Morris, IL
#7
waste said:
Steve, there is also the chance that one, or more, of the 'laterals' in the bottom of the filter has a hole in it and you're not keeping the sand in the filter the way it should be :cry:
That is actually what I was afraid of. But it only seems to happen after I backwash, maybe. I did not notice it for a while, then I vacuumed, it hadn't been done for a week and the last time I had vacuumed I did not backwash for very long. This time I had filled my pool over full with the intent on vacuuming, and backwashing really good. Well, the next day, the sand was in the bottom. I will just have to pay attention, I want to try the rinse method and see if that works.
 
May 25, 2007
10
#8
I have always gotten a little 'sand' in my pool, and by a little I would say that in a week, it wouldn't be any more than a tablespoon or two. This doesn't come from my filter however, it comes from the pool deck.

I get more of this 'sand' after rain. It mostly ends up around the edges and up on the steps. I've always attributed it to loose sand in the concrete.

Over the years (5 years now) it's gotten less and less. Could this be a possiblity for you as well?

My sister-in-law has a similar issue on her pool, but here's is due to having an idiot for a pool builder. Her PB sloped her cocrete toward the pool on two sides. It was our of sheer lazyness that this was done, but none the less. She ends up with lots of dirt, and grit from the deck in her pool. She also had a heck of a time keeping her pH balanced from the water running over the deck an into the pool. . .