Should I change my filter sand?

[CaptainHowdy]

Long story short....a little less than 2 years ago, I had algae problems with Baquacil, and drained the pool pretty much, and converted to chlorine. Had to beat the sand to get it out, all clumped. Broke laterals, replaced...bought Quikrete pool sand from Home Depot. Last year, the water was never very clear and I fought algae a couple times. This year I opened the pool...the day I started it up, the pump motor died (it was only 4 years old) I replaced it.

I had to backwash a couple times a day because I'd lose skimmer suction and all jet power if I didn't. I looked inside the filter. Sand was not clumped or look dirty. But used sand cleaner and let it sit, backwashed and rinsed... I did this 3 days ago and have not had to backwash. Water is slightly more clear but not that clear, I can't see the pattern of the liner. It's not algae. Wondering, should I change my sand? With pool store sand of course this time, if I do. Trying to see if this Home Depot sand is the issue.

[PoolDoc]

...bought Quikrete pool sand from Home Depot.

Wondering, should I change my sand? With pool store sand of course this time, if I do. Trying to see if this Home Depot sand is the issue.

As far as I know, Quikrete doesn't bag or sell filter sand. They DO sell both play sand and masonry sand. Masonry sand would do a great job of filtering . . . until the fines clogged your laterals, and tore up your multiport valve. Since that hasn't happened, I'm guessing you bought play sand, which is much too coarse, and would result in poor filtration, but low filter pressures.

Yes, you probably should change the sand.

[CaptainHowdy]

Thanks Pooldoc! It says pool filter sand on the bag, here is the product. http://www.homedepot.com/p/Quikrete-50-lb-Pool-Filter-Sand-115350/202314677 But I was thinking it may be best safe than sorry too....does that link tell you anything?

[BigDave]

Looks like HD does sell Quikrete pool sand (http://www.homedepot.com/catalog/pdfImages/f2/f2a36010-2bdb-4d6f-b6a0-1e285c221bd6.pdf) although the particle size range (0.85-0.425 mm) exceeds the manufacturer's recommendation for my filter (.45mm - .55mm) at both ends.

[PoolDoc]

Thanks Dave;

@ CaptainHowdy: my bad; I should have checked. I doubt that Quikrete would call it pool sand, and bag something else, so I'm satisfied it *is* pool filter sand.
Time to back up, and go at it again.

Sand filters tend to fail to filter for (2) reasons:

1. Wrong sand (which we've ruled out.)
2. Too little sand, which should be checked.
3. Pump too big for filter, resulting in dirt being pushed THROUGH the filter.

Can you -- or have you already -- verified that the sand is at the proper level in the filter?

Assuming that your answer is "yes!", there are two further steps you can take:

1. Send us the make/model of both pump (not electric motor ON pump) and filter, so we can match them up.
2. Do the DE test. Get a small bag (or large -- it's not that expensive) bag of DE. Put 2 cups of DE filter powder in the skimmer while the pump is on, and the skimmer operating. Check the pool return: if DE shoots back into the pool, your filter is not working properly. If it does NOT, then your filter is working, and the DE will help filter whatever's clouding your pool. However it will also make the filter stop up much more quickly. If you like, you can add more after each backwash, till the water is clear.

[CaptainHowdy]

Thanks guys....I had concern after reading online reviews for that sand, several people had problems. The pump I bought last week (I am still concerned why the old one failed after less than 4 years) It got very hot and only hummed at the end. It's a Milennium 2 HP, 2 speed. I have a 24 foot above ground pool...the filter is a 22 inch milennium ball. I thought about painting it yellow and making it a minion, lol. Yes, in fact, when I put the sand in back in August 2012 I put water at the bottom of the filter, and put in 4 bags of sand....it was filled to the widest point of the filter, not to the top, per the instructions of the pool store. What is a DE test?

[Watermom]

The DE test is what PoolDoc described in step 2 of his post above. It checks to see if your filter is working correctly. If, after adding the DE, you see it shooting out of the return jet, you know that you have a filter that is not working properly.

[CaptainHowdy]

I get that, I just have no bloody idea what DE is, lol.

[Watermom]

DE is Diatomaceous Earth and is dust made from the fossilized remains of diatoms, a type of hard-shelled algae. It is the filter media that is used in DE filters. Many of us who have sand filters use it to help filter out the really tiny dust that the sand won't catch. And, we also suggest throwing a handful in when there is a question of whether a sand filter is working properly or not. You can buy it at a pool store and maybe at Lowe's or someplace like that.

Adding DE to a Sand Filter (http://www.poolforum.com/pf2/showthread.php?t=3742)

[CaptainHowdy]

Gracias :)

[Watermom]

De nada! ;)

[CaptainHowdy]

I ended up going to the pool store with a sample of the leftover sand I have, I definitely see a different in the consistency....I will post photos later. I'm a photographer, so that part is easy, lol. I decided to just change it, here it goes.

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Bummer, I don't see a way to upload an image....the Quikrete definitely looked more coarse.

[CaptainHowdy]

https://scontent-b-atl.xx.fbcdn.net.KILLED/hphotos-frc3/t31.0-8/10321667_10152114909874639_6045255724211426912_o.j pg

https://lh4.googleusercontent.com/-0k_GzIcq39U/U2VcN4_D7jI/AAAAAAAAG_A/Kt__rDz7FqU/s720/sand.jpg

[PoolDoc]

https://lh4.googleusercontent.com/-vejQ_QPRStU/U2VeUxqHeYI/AAAAAAAAG_Q/YMfHswiwZBs/s587/sand%2520labeled.jpg

https://lh3.googleusercontent.com/-zZO1ky7B0BA/U2VgOxvyK-I/AAAAAAAAG_g/lOS6vmExy8w/s1024/detail.jpg

VERY helpful pictures.

But it looks like your mystery is solved: Quikrete was selling "pool sand", but they were bagging something else. Let us know how it goes with the new sand.

[CaptainHowdy]

Email sent, please share here if it helps :) Thanks, now hoping it clears water soon :D

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from email:

Thank you. What main difference do you see? I thought sand is sand right, esecially if it says pol filter sand on the bag. To me it looks more coarse than the pool store sand I bought today. Wondering if that's why my last pump burned out.

[PoolDoc]

Because the filter sand was still damp, it was a bit hard to compare. But what I noticed was that the largest visible particles in the Quikrete were larger than the largest particles in the than the Palmetto sand. Filter sand is *supposed* to be evenly graded, with 90+% of the particles ranging from 0.018" to 0.020". Honestly, neither sand appeared to meet that specification to me, but the Palmetto sand seemed a bit finer, and I know from experience that fine sand produces clearer water than coarse sand.

"Sand to be No. 20 standard silica (uniformity coefficient not greater than 1.75) .018-.020 in diameter particle size"
http://www.pentairpool.com/pdfs/TritonIIOM.pdf

"Grain size 20/40 mesh is most widely used. 90% of the sand is to fall within the specified particle range. Not more than 1% of the total sample
can fall on the first or last sieve in the series. Clay and silt size particles >105 microns are removed with the processing, as well as weak and crusted grains."
http://www.eqb.state.mn.us/documents/23.%20March%20Final%20Silica%20Sand%20report.pdf

[CaptainHowdy]

No no, the samples were both un used, the Quickrete stuff was from inside the bag, leftover stuff I didn't use. Both bags had some condensation in them though, but this wasn;t sand that came from my filter.