Sand in Bottom of pool?

[mysticgraces]

Hi All
Iam a newbie and on two occasions have noticed some sand at the bottom of our pool...it generally happens after vacuming or backwashing..Is this the sand from our filter? and does this mean there is a huge problem?

Thanks!

[Poconos]

You can find out if it sand or a fine silt easily. Stir up the water near it with a net or something. If it disperses easily it's silt. Sand will settle right out again. Or, go down and see if you can pick some up with your fingers or just rub it. Sand will be gritty, you won't even feel the silt. I call it silt as it could be from your fill water or even pollen during the right season. It may be so fine it goes right through the filter. Some of us put a little DE powder in the filter to trap finer stuff. Identify what the stuff is first then we'll go from there.
Couple other things...after you backwash do you do a 'rinse' for a few seconds before switching to 'filter'? Also, what make/model filter and pump size? Have to make sure the pump and filter are sized correctly.
Al

[mysticgraces]

Hi Al

From what you describe its silt..its very fine and disperses when touched.We werent doing a rinse,after a backwash,but after reading the posts here,last night we did do a rinse..

[mona_weaver]

I am having the same problem, except for sure it is sand, not silt.
The sand is located in the same area as my water return, so I assume
it is coming from the sand filter. Any ideas on what could be wrong?

thanks!
Mona

30' AG - 2 years old:(

[matt4x4]

Mona, you should do a new post when asking a new question - you'll be guaranteed and answer then.
Sand could mean a cracked lateral or a bad seal on the standpipe up the middle of the filter unit where it seals with the multiport valve or just too much sand inside the unit. Sand level should come up to where the filter body starts to curve inwards from it's widest point at the top.
Also, if you just got the pool and filter installed or recently changed your sand, it is sometimes quite normal to see some sand escaping for the first while.

To eliminate fine silt which can easily work it's way through a sand filter only to deposit itself back in your pool, try using a cup or two of DE (2 lb increase in pressure) in your filter (adding it slowly through the skimmer) before vacuuming your pool

[mona_weaver]

thanks so much for the advice.

[Poconos]

On the DE trick, mix in a pail of water first and add slowly like Matt said. After adding a little, check the pressure after 15 or 20 minutes as it takes time for the DE to settle where it should be and the pressure to rise. If the pressure didn't go up enough, add more. Once you know how much it takes then you can mix and dump that amount at once.
Al