Cloudy! SUPER fine sand. Help!

Bqtk

Member
Jun 16, 2019
23
Belleville, ontario
I added new sand to my filter, and than ran it without rinsing/backwashing first. Now I've learned that you must, because new sand has super fine particles that get suspended. Surprise, surprise, my pool got super cloudy almost immediately after making this mistake.

I'm still convinced it's sand because it feels grainy, not slimy. I used panty hose on my skimmer, and when I take it out and let it dry, it's full of crusty fine sand.

Question is how to I get rid of it? It's super fine and sits on the surface and is mixed in down bellow. Not too much settles on the bottom each day?

I realized flocc is hated, for good reason, but is there any other way?

(PS: I SLAMed just to be sure :p).

Thanks in advance!
(Mods feel free to move if I'm in the wrong section).
 
If it's settling very slowly or floating on the surface, chances are it isn't sand from the pool filter. Next time you collect some in a skimmer sock, put some in a small plastic container a put a little muriatic acid on it to see if it fizzes.

Post a full set of current test results from your own test kit.

What chemicals have you added in the past few weeks?
 
Very slowly. Initially a lot settled but now it's a tiny amount each day. It seems so fine that it's happy to be suspended. Is this common if you don't rinse your new sand before using?


I have no experience with it.

One option might be to add some DE to your sand. Search this site for the "how to" of adding. The idea of it is that the DE improves the filtering ability of the sand, allowing the filter to trap smaller particles. I have no promises that it will work, but it certainly will not hurt anything. It will still take some time for it to filter all of it out.

This year, I started adding a few cups of DE to my filter after I backwash. It definitely reduces the very fine particles you see in the pool when the lights are on at night. Just make sure you use DE for pools, not the gardening/insect prevention variety.

Cellulose fiber does the same thing as DE. It allows the filter to trap smaller particles.

I assume you used pool grade sand correct?
 
If it's settling very slowly or floating on the surface, chances are it isn't sand from the pool filter. Next time you collect some in a skimmer sock, put some in a small plastic container a put a little muriatic acid on it to see if it fizzes.

Post a full set of current test results from your own test kit.

What chemicals have you added in the past few weeks?

CYA, borax, and A&H baking soda. Also started using 70% CH in place of bleach. Could that be it?

I assume you mean add acid to some dried particles from the sock?

Will test and post soon.
 
I have no experience with it.

One option might be to add some DE to your sand. Search this site for the "how to" of adding. The idea of it is that the DE improves the filtering ability of the sand, allowing the filter to trap smaller particles. I have no promises that it will work, but it certainly will not hurt anything. It will still take some time for it to filter all of it out.

This year, I started adding a few cups of DE to my filter after I backwash. It definitely reduces the very fine particles you see in the pool when the lights are on at night. Just make sure you use DE for pools, not the gardening/insect prevention variety.

Cellulose fiber does the same thing as DE. It allows the filter to trap smaller particles.

I assume you used pool grade sand correct?
Yes, bought it at a pool shop.
Thanks, I'll see if I can find some local pool-DE.

Side question: I just started using a solar cover. Should I stop, giving that warmer water will dissolve more particles?
 

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70% CH? What exact product is that? CH stands for Calcium - which isn't a substitute for chlorine.
Since you have an above ground pool, I assume it has a vinyl liner. Is that correct?

How did you get 0.7 for CC and 95 for CH?

When you report results, please use the format

FC
CC
pH
TA
CH
CYA
Water Temp

As it makes it easier for us to read and keeps everyone on the same page.
 
70% CH? What exact product is that? CH stands for Calcium - which isn't a substitute for chlorine.
Since you have an above ground pool, I assume it has a vinyl liner. Is that correct?

How did you get 0.7 for CC and 95 for CH?

When you report results, please use the format

FC
CC
pH
TA
CH
CYA
Water Temp

As it makes it easier for us to read and keeps everyone on the same page.

Sorry! By CH I meant calcium hypochlorite. I switched from liquid bleach to 70% calcium hypochlorite around the time that I changed the sand. Could this be calcium flakes? My chemistry doesn't support it but, but they seems to match the description (flimsy white flakes that dry out my skin and dusty-crust on equipment), and the calcium hypochlorite doesn't dissolve well (always have some sitting on the bottom).

These numbers should be much more accurate. I took the other one before giving the pump much time.

FC 8
CC <0.1
pH 7.7
TA 90
CH 90
CYA 30
Water Temp 22.5°C

These numbers have been stable since the issue suddenly began 2 weeks ago (with the exception of pH creeping up and FC responding to adding calcium hypochlorite).
 
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Ah - 70% Cal Hypo.... that makes more sense.

I have never used Cal Hypo so can't advise if it could precipitate calcium flakes. Let me get some more eyes on this - @mknauss @ajw22 . In the mean time, don't put any acid on the flakes or "sand" - as they may (or may not) still contain chlorine. Acid and chlorine in direct contact is not a good thing.
 
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Cal Hypo can cause cloudiness. My first step would be to switch immediately back to liquid chlorine and give it a few days to clear up.

If that fails, I would add a small amount (enough to get a 1-2 psi increase on the pressure gauge) of DE to the sand filter and see if that cures the problem,
 
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Thank you both.

A few updates:
-I followed the acid advise before reading your post! Really wish I hadn't now. But for what it's worth it did immediately fizzed up.
-Here's a picture of the small white particles. Since I caught them in my backwash, I assume I can slowly filter it out.
 

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It's not the fizzing I was concerned about - the fizzing denotes the calcium reacting with the acid. I was most concerned about the acid reacting with any chlorine residual left from the Cal Hypo. Mixing acid with chlorine in any form is dangerous.

Yes, your filter can and will filter the particles out. Adding DE as Dave recommended will increase that filtering ability. Keep your water in balance and have POP (Pool Owner Patience). Keep us apprised of your progress.
 

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