- Jul 19, 2015
- 110
- Pool Size
- 18000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool Universal40
Hello TFP, this is my first post over in this section. Sorry if this post goes in a few different directions, but I'm trying to diagnose an issue here.
One year ago this month, we filled our newly built plaster pool. This is our second plaster pool, so I'm somewhat familiar with pool upkeep and maintenance.
A few weeks ago, I began to notice some light brown/tan build up in the pool. Its only on the bottom/steps, not on the sides. Being that this is a newer pool, there are still some unique patterns in the plaster, and the tan spots seem to almost take the same shape of some of those patterns, almost like it will adhere to some of the plaster, but not all (hope that makes sense).
The reason I'm posting in this section is because I found out today my electronic PH gauges are way off (less than 1 year old). I purchased two, each a different brand. All winter long, they've both been consistent around 7.6 - 7.8. I haven't used the comparator lately because both testers are within .1 of each other consistently, so I assumed there was no problem. Around November 2023, I've finally been able to stop adding huge amounts of MA to keep the PH down.
Yesterday, I used the comparator and the PH was off the charts, but both electronic testers showed 7.9. I went to a neighbors today and his electronic tester showed about 1.5 PH higher than both of mine. So, I came home and re calibrated one of them so I could compare.
Long story short, for the past 5-6 months, my PH has been closer to 8.5 to 9 rather than 7.5 to 8. I am curious if that high PH could have anything to do with these brownish spots.
We do not have a pool vac or robot. I vacuum it out about once a week, or the day after a storm. Naturally, we get a lot of dust this color in the Vegas area. I'm also curious if there's any way the dust/dirt is adhering to the plaster. I don't believe they are stains because they are cleaned off with pumice (plastic or stainless brush don't seem to help).
Current numbers -
FC 3.0
CC 1.0
CH 800 (water change coming soon)
TA 90
CYA 70
Salt 3500
Please see the pictures below -
This is a sample area on the top step of our swim out. It actually looks worse on camera than in person, but I'm glad it shows up. The whole pool isn't like this, this is one of the worst areas.
And this is the same area after about 20 seconds of a pumice stone. The patterns are still there from the plaster curing, or whatever the term would be, but the tan is pretty much gone -
So my questions -
Anyone know what it is?
Do I need to use pumice on my whole pool? Or will lower PH for a few weeks maybe eat it away?
Was it maybe caused by high PH for the past few months?
Thank you in advance, sorry for the long winded post!
One year ago this month, we filled our newly built plaster pool. This is our second plaster pool, so I'm somewhat familiar with pool upkeep and maintenance.
A few weeks ago, I began to notice some light brown/tan build up in the pool. Its only on the bottom/steps, not on the sides. Being that this is a newer pool, there are still some unique patterns in the plaster, and the tan spots seem to almost take the same shape of some of those patterns, almost like it will adhere to some of the plaster, but not all (hope that makes sense).
The reason I'm posting in this section is because I found out today my electronic PH gauges are way off (less than 1 year old). I purchased two, each a different brand. All winter long, they've both been consistent around 7.6 - 7.8. I haven't used the comparator lately because both testers are within .1 of each other consistently, so I assumed there was no problem. Around November 2023, I've finally been able to stop adding huge amounts of MA to keep the PH down.
Yesterday, I used the comparator and the PH was off the charts, but both electronic testers showed 7.9. I went to a neighbors today and his electronic tester showed about 1.5 PH higher than both of mine. So, I came home and re calibrated one of them so I could compare.
Long story short, for the past 5-6 months, my PH has been closer to 8.5 to 9 rather than 7.5 to 8. I am curious if that high PH could have anything to do with these brownish spots.
We do not have a pool vac or robot. I vacuum it out about once a week, or the day after a storm. Naturally, we get a lot of dust this color in the Vegas area. I'm also curious if there's any way the dust/dirt is adhering to the plaster. I don't believe they are stains because they are cleaned off with pumice (plastic or stainless brush don't seem to help).
Current numbers -
FC 3.0
CC 1.0
CH 800 (water change coming soon)
TA 90
CYA 70
Salt 3500
Please see the pictures below -
This is a sample area on the top step of our swim out. It actually looks worse on camera than in person, but I'm glad it shows up. The whole pool isn't like this, this is one of the worst areas.
And this is the same area after about 20 seconds of a pumice stone. The patterns are still there from the plaster curing, or whatever the term would be, but the tan is pretty much gone -
So my questions -
Anyone know what it is?
Do I need to use pumice on my whole pool? Or will lower PH for a few weeks maybe eat it away?
Was it maybe caused by high PH for the past few months?
Thank you in advance, sorry for the long winded post!
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