Help the pebbles in the finish are coming off in the spa.

May 24, 2014
34
Dunellen nj
The pool was installed in 2013 by Anthony and Sylvan, white plaster finish. We had bond failure and had to have the pool replastered. We had the pool replastered by Anthony and Sylvan in 2016 using a pebble finish. We have continued to have high CH, over 400 we have replaced 1/2 of the water and it still climbs. Last year when we opened the pool the spa had started to develop grey scale nodules, which I continued to brush off, the scale finally stopped. Last year we also noticed the pebbles in the spa falling off when you pass your hand over the surface. A&S had no answers or a solution for the pebble loss. This year we opened the pool to the same issues, scale and pebbles falling off. The odd thing is, it is not happening on the surface of the pool, just the spa. Which believe me I’m happy about.
Does anyone have any answers for why this is happening??
Thank you!
Susan Rossi.
 
To answer that question we would need a complete history of your water chemistry. But let’s start with your current water chemistry from your own test kit…

FC
CC
pH
TA
CH
CYA
SALT
Water temperature

How do you chlorinate your pool?

What chemicals do you use in your pool and spa?
 
To answer that question we would need a complete history of your water chemistry. But let’s start with your current water chemistry from your own test kit…

FC
CC
pH
TA
CH
CYA
SALT
Water temperature

How do you chlorinate your pool?

What chemicals do you use in your pool and spa?
The pool was opened on Monday so my water chemistry isn’t where it should be yet.
FC 0
CC .1
PH 7.2
Alk 40
Cyn 40
CH 400
Temp 67

I’m using trichlor now, but have a salt system which I can’t start yet. The pool company that opened said ALK was 85, which is why I test my water.
We had a couple days of significant wind and I just added an oxidizer to the pool to burn off anything.
 
TFtest kits the K2006 I believe.
TFKIts makes the TF-100.

Taylor makes the K-2006C.

You have low pH and low TA and probably low CSI which will etch you plaster. If this is the way you have run your pool chemistry the last few years the low CSI would have etched away the plaster around the pebbles causing them to loosen.

Do you have PoolMath to calculate your CSI?

Have you read ABCs of Pool Water Chemistry?

 
TFKIts makes the TF-100.

Taylor makes the K-2006C.

You have low pH and low TA and probably low CSI which will etch you plaster. If this is the way you have run your pool chemistry the last few years the low CSI would have etched away the plaster around the pebbles causing them to loosen.

Do you have PoolMath to calculate your CSI?

Have you read ABCs of Pool Water Chemistry?

Thank you, ordinary my pH is within a normal range, but why just the spa? I will re-read pool math.
 
Spa is a smaller body of water and problems can show us there first. Problems may be brewing in your pool but not visible yet.
 
Spa is a smaller body of water and problems can show us there first. Problems may be brewing in your pool but not visible yet.
Thank You!
I will concentrate on using the pool math app i downloaded getting the pools TA up and other chemicals in line. If I add baking soda to the pool to raise the TA will that raise the pH too, I struggle with keeping the pH in check once I start the salt system.
 
Describe how you manage your pH and TA?

When do you lower your pH to what target?

What is the pH and TA of your fill water?
 

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Describe how you manage your pH and TA?

When do you lower your pH to what target?

What is the pH and TA of your fill water?
I test the water daily, I primarily use the Taylor kit, but have the TFtest kit too. I lower my pH with muriatic acid. I had been having an ongoing problem with the TA being too low. I will use baking soda in the future to raise the TA thanks to this forum, in the past I would use products from the pool store. I have not tested my house water for pH or TA, but I will.
 
I test the water daily, I primarily use the Taylor kit, but have the TFtest kit too. I lower my pH with muriatic acid. I had been having an ongoing problem with the TA being too low. I will use baking soda in the future to raise the TA thanks to this forum, in the past I would use products from the pool store. I have not tested my house water for pH or TA, but will. I would lower the pH when it got to about 7.8, which was frequently because I have a salt generator, which I’ve not started yet this year.
 
I test the water daily, I primarily use the Taylor kit, but have the TFtest kit too. I lower my pH with muriatic acid.

Numbers please.

What pH do you let it go to before you lower it?

What pH do you target when you add acid?

I had been having an ongoing problem with the TA being too low. I will use baking soda in the future to raise the TA thanks to this forum, in the past I would use products from the pool store. I have not tested my house water for pH or TA, but I will.

I think you are adding too much acid and trying to keep too low a pH which is affecting your TA.

Your TA should stabilize between 50 to 70 if you are managing your pH correctly.
 
Numbers please.

What pH do you let it go to before you lower it?

What pH do you target when you add acid?



I think you are adding too much acid and trying to keep too low a pH which is affecting your TA.

Your TA should stabilize between 50 to 70 if you are managing your pH correctly.
I may very well be trying to keep the pH too low, I think you’re right. I typically added acid when it got to 7.8 and certainly above that number. I would say in the past i was happy with a 7.2 reading. I’ve relied on pool company advice.

I also have the pool company out all winter, I’m in NJ, to test the pH and add acid to avoid a repeat of the scale issue a few years ago. Could that be the start of a spring issue for the past couple years? When the cover was removed the spa had the start of some grey scale nodules and of course the shedding of pebbles.
 
I may very well be trying to keep the pH too low, I think you’re right. I typically added acid when it got to 7.8 and certainly above that number. I would say in the past i was happy with a 7.2 reading. I’ve relied on pool company advice.

It is often best to keep pH between 7.6-7.8. Depending on your oerall water chemisrty 7.2 can be too low.

Pool companies don't understand about the effects of CSI and etching.

I also have the pool company out all winter, I’m in NJ, to test the pH and add acid to avoid a repeat of the scale issue a few years ago. Could that be the start of a spring issue for the past couple years? When the cover was removed the spa had the start of some grey scale nodules and of course the shedding of pebbles.

Was the pool company adding acid to the spa during the winter?
 
It is often best to keep pH between 7.6-7.8. Depending on your oerall water chemisrty 7.2 can be too low.

Pool companies don't understand about the effects of CSI and etching.



Was the pool company adding acid to the spa during the winter?
Yes the pool company came out monthly and added acid if the pH was high, they were testing the water each time. They would sometimes put in a pump to circulate the water after the acid addition, not sure if that was always done, but I doubt it. I’ve had this winter testing for a while especially after removing the cover to find scale all over the pool. Just to be clear, I’m not a young woman so this process was difficult for me.
Do you happen to know of a good pool company in central New Jersey?
 
It is often best to keep pH between 7.6-7.8. Depending on your oerall water chemisrty 7.2 can be too low.

Pool companies don't understand about the effects of CSI and etching.



Was the pool company adding acid to the spa during the winter?
Yes the pool company did add acid to the pool and spa. From time to time I saw them put a pump into the pool/spa to circulate the water, maybe to pump pool water from the pool to the spa, I’m not sure.
 
Yes the pool company did add acid to the pool and spa. From time to time I saw them put a pump into the pool/spa to circulate the water, maybe to pump pool water from the pool to the spa, I’m not sure.
Unfortunately, I do not.
The pool water is balanced, but I’m still losing pebbles when I run my hand over the spa walls. Just vacuumed the spa and there was about 1/4 + cup of pebbles in the vacuum bag.
Any ideas about what to do? I’m hoping it will stop in time, but still worried.
CSI 0.01
PH 7.7
TA 80
FC 3.0
CYA 55
CH 375
Temp 70
 
The pool water is balanced, but I’m still losing pebbles when I run my hand over the spa walls. Just vacuumed the spa and there was about 1/4 + cup of pebbles in the vacuum bag.
Any ideas about what to do? I’m hoping it will stop in time, but still worried.

Nothing you can do. The plaster anchoring the pebbles is missing. Nothing will replace it. The pebbles will continue coming loose in areas without sufficient plaster.
 

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