(Update) Sand (dirt?) in pool, any other cause besides busted lateral/lateral assembly?

Baker25

Well-known member
Jul 1, 2018
70
Roscoe, IL
Saw what I am pretty sure was sand in pool. Put sock over return, no more sand or sediment so I replaced lateral assembly. Did not see anything wrong with old assembly, but replaced anyways. Less suspected sand but still a good amount around with the run time of about 6 hours. I figured this was just environmental (sediment) and not sand. The last two days I have ran the pump just enough to circulate the chlorine. Hardly any suspected sand/sediment in the pool, maybe half a tea spoon. So with the pump barely running, but with the same environmental conditions such as wind etc, I am seeing nearly 99% less sediment in the pool. So I believe something still isn't right with the filter and what I am seeing is in fact sand. What else could it be?
 

YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
14,421
Evans, Georgia
Can you pick the sand up and feel it, or does it blow away? Certainly sounds like algae, which people often mistake for sand.
Can you provide us with a set of test results:
FC
CC
pH
TA
CH
CYA

We may be able to spot a problem then....

Maddie :flower:
 

Baker25

Well-known member
Jul 1, 2018
70
Roscoe, IL
I can get my fingers on it and feel it.
Yesterday the CYA was probably 30 where I try and keep it. FC was 4 so I bumped it to 6 like I do every night. Average about a 2 FC loss over 24 hours. My pH runs a little high closer to 7.8-8. I’m on well water so our alkalinity is always high. Never had a positive for CC. Drop the 5 drops into the tester, never had a color appear, always stays clear. Tested it the other day. I don’t bother with CH. I’ve had this sand/sediment since day one. Just realized recently that it might not be dirt that was floating around in the air.
 

MyAZPool

Gold Supporter
Jul 3, 2018
1,515
Arizona
I was talked into zeosand when I installed my pool and had the same issue. Do you have typical filter sand or one of the zeolite varieties? I recently changed to good old #20 silica and the sand on the floor disappeared.
Tpopz
Just curious. Are you suggesting that if the OP is actually using a zeolite type product, that is the reason that he/she has sand in their pool?
Thanks...
r.
 

Tpopz

Bronze Supporter
Jun 4, 2019
74
Versailles, Kentucky
Tpopz
Just curious. Are you suggesting that if the OP is actually using a zeolite type product, that is the reason that he/she has sand in their pool?
Thanks...
r.
It’s a possibility.

I guess some varieties of zeolite are extremely brittle and somewhat fragile. Pool store who talked me into the zeo suggested I cover the laterals with pea gravel, then reinstall the zeo. My complaint wasn’t their first.
 

MyAZPool

Gold Supporter
Jul 3, 2018
1,515
Arizona
Tpopz
Thanks. Yea, I don't know. I guess anything is possible.
Personally, I use a 50/50 mix of silica and zeo in a 12 year old monster commercial Pentair sand filter and I have never had a grain of sand in my pool (as far as I know anyway).
When it's time for a media change, I think that I am going to consider glass. Some positive reviews on that so far. But for me, the jury is still out on that, so I will "wait and see'. I just changed the media in 2016, so I've got some time to decide.

Thanks again and take care.
r.
 

Baker25

Well-known member
Jul 1, 2018
70
Roscoe, IL
I used hth pool filter sand as suggested in numerous posts on this site. I just feel like if it is an issue with the filter, there is a seal or gasket going bad. I know there are only a few in the entire system. I went out and vacuumed my pool and when I did so, I slipped in as to not disturb anything. I walked around very slowly with goggles like I always do and got everything I could see. Finished up, swam for 45 minutes and got out. Went back an hour later and there is a ton of sand/sediment on the pool bottom. This would have been with the pump running for about 2 hours at that point. I expect some dirt from dirty feet, but this is way more than is reasonable.
 

Baker25

Well-known member
Jul 1, 2018
70
Roscoe, IL
I decided to do the sock test again, and like I feared, no new sand or sediment in the pool. By this point without the sock, I would have had quite a bit, but the bottom is crystal clear. So, is there anything in the valve assembly that could be broke? I guess I could take the lateral assembly out again but I've already replaced it once? The pump is a Hayward SP1592 and the filter is a Hayward s180t. From what I can tell, both items are fine for my 12,700 gallon AGP. I'm at my witts end with this. I might just go buy a new filter.

Edit: What I am seeing on the pool floor is not the same color as the filter sand I put in. It actually is a "dirt" brown color.
 
Last edited:

Baker25

Well-known member
Jul 1, 2018
70
Roscoe, IL
how about some photos? pool floor with sand and maybe some close up with some of the sand in your hand?
Negative, can't collect it in my hand as there is not enough in one spot. It's not like a huge mound of dirt/sand in pile. Pictures won't be clear enough to matter. Thanks.
 

Baker25

Well-known member
Jul 1, 2018
70
Roscoe, IL
This morning I backwashed the filter, rinsed and put it back on filter. Took the sock off and within one hour, there was more sediment on the pool floor. Nothing prior to this. So again, what could be the issue?
 

IceShadow

Gold Supporter
TFP Guide
Jun 8, 2019
2,177
Milwaukee, WI
I've had this before and thought it was sand - took apart my filter, didn't find any issues with the standpipe or the lateral. Ended up just being some dust/dead algae gathering at the bottom. It only did it when the pump is on - my theory is that it was spread out evenly over the surface while the pump was off, and thus not visible, and the pump running caused water currents that made it gather together.
 

Baker25

Well-known member
Jul 1, 2018
70
Roscoe, IL
I've had this before and thought it was sand - took apart my filter, didn't find any issues with the standpipe or the lateral. Ended up just being some dust/dead algae gathering at the bottom. It only did it when the pump is on - my theory is that it was spread out evenly over the surface while the pump was off, and thus not visible, and the pump running caused water currents that made it gather together.
Would the pump running all of a sudden cause all the surface dust/dirt to fall to the bottom of the pool? Is your theory that when the dust/dirt gathered together it became heavy enough to sink? This would make sense in that over the course of 12 hours, dust was on the surface of the water. It was obvious in the bright sun reflecting off the water. With the sock on the return, there wasn't much circulation and it was basically stationary. I might just replace the spider gasket as I see conflicting answers if this could be a reason why. If that doesn't fix it, then either the new lateral I put in is broken or your theory is correct.
 

IceShadow

Gold Supporter
TFP Guide
Jun 8, 2019
2,177
Milwaukee, WI
My theory is that there's dead algae or some dust that blew on on the bottom of the pool fairly evenly spread out so you can't see it. The pump runs, the water starts moving, and the water at the bottom of the pool sweeps over the material and pushes it together in piles. Mine formed at the corners of the deep end and on the "ledge" where the shallow end started going down toward the deep one.
 
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Baker25

Well-known member
Jul 1, 2018
70
Roscoe, IL
My theory is that there's dead algae or some dust that blew on on the bottom of the pool fairly evenly spread out so you can't see it. The pump runs, the water starts moving, and the water at the bottom of the pool sweeps over the material and pushes it together in piles. Mine formed at the corners of the deep end and on the "ledge" where the shallow end started going down toward the deep one.
I could possibly buy into this idea, and maybe that is part of it. However, I could have the pump running for a few hours, manually vacuum, keep the pump running, and within a few hours the sediment is back on the pool floor. This makes me think the sediment is being reintroduced into the pool via the return.
 

IceShadow

Gold Supporter
TFP Guide
Jun 8, 2019
2,177
Milwaukee, WI
It very well could be. Have you checked the sand in the filter to see if it's clumping? Perhaps it's not filtering out the dead algae / dirt / dust from the pool due to channeling through the sand.
 

Baker25

Well-known member
Jul 1, 2018
70
Roscoe, IL
It very well could be. Have you checked the sand in the filter to see if it's clumping? Perhaps it's not filtering out the dead algae / dirt / dust from the pool due to channeling through the sand.
It’s fresh sand from when I put in the new lateral umbrella assembly. I also noticed a bit ago upon inspecting the socks, I saw little blades of grass and little shards from the sand imbedded in the inside fabric of the sock. Meaning it only could have come from the return jet.
 

IceShadow

Gold Supporter
TFP Guide
Jun 8, 2019
2,177
Milwaukee, WI
OK - perhaps it is your MPV then. Maybe it's leaking over to the return while skipping the filter?

You haven't backwashed recently, have you? Are you setting the MPV to rinse for 30-60 seconds after you backwash?
 

Baker25

Well-known member
Jul 1, 2018
70
Roscoe, IL
OK - perhaps it is your MPV then. Maybe it's leaking over to the return while skipping the filter?

You haven't backwashed recently, have you? Are you setting the MPV to rinse for 30-60 seconds after you backwash?
Today was the first time I backwashed after changing the lateral and sand. Followed up with a 30ish second rinse. I only did the backwash and rinse just to see if it would prevent sediment from coming back in the pool which it did not.