New plaster now stained

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BoHpool

BoHpool

Gold Supporter
Jun 24, 2022
157
Donna, TX
Pool Size
37500
Surface
Plaster
Chlorine
Liquid Chlorine
The first 2 pictures are of the new plaster May 28. The last 4 pictures are of the stained plaster yesterday. I followed the TFP new plaster start-up as well as I could. I have a helper who works every other week. I have tried to get him to read and follow directions but he seems immune. I turned the pools over to him July 3rd and the spa was still bright blue with good chemistry. It's a bromine spa. I assume the staining is copper from the heater.
FC 7
pH 7.6
TA 80
I took back over on July 10 and noticed immediately the staining in the spa. I tried to test the chemistry but got strange results.
FC 10
pH purple
TA I added 2 drops of 7 and started adding 8, the sample turned red, I added 2 drops of 9 and it got brighter red and stopped
I used pool math and added half of the baking soda recommended. I waited a few hours and tested pH again. Still purple. I used pool math and added half the recommended dray acid. I repeated this process till I got the TA and pH back to 80 and 7.6.
So I have the spa back in shape chemistry wise but it looks like heck.IMG_20230528_113935388.jpgIMG_20230528_113945937.jpgIMG_20230712_103337733.jpgIMG_20230712_103345575.jpgIMG_20230712_103356399_BURST000_COVER.jpgIMG_20230712_103403394.jpg
 
Last edited by a moderator:
BoHpool said:
I have a plaster spa. Does this advice apply to a plaster spa also?
Click to expand...

I believe so, but what specific advice are you asking about?

Do you have a spillover spa to your pool?
 
BoHpool said:
The first 2 pictures are of the new plaster May 28. The last 4 pictures are of the stained plaster yesterday. I followed the TFP new plaster start-up as well as I could. I have a helper who works every other week. I have tried to get him to read and follow directions but he seems immune. I turned the pools over to him July 3rd and the spa was still bright blue with good chemistry. It's a bromine spa. I assume the staining is copper from the heater.
FC 7
pH 7.6
TA 80
I took back over on July 10 and noticed immediately the staining in the spa. I tried to test the chemistry but got strange results.
FC 10
pH purple
TA I added 2 drops of 7 and started adding 8, the sample turned red, I added 2 drops of 9 and it got brighter red and stopped
I used pool math and added half of the baking soda recommended. I waited a few hours and tested pH again. Still purple. I used pool math and added half the recommended dray acid. I repeated this process till I got the TA and pH back to 80 and 7.6.
So I have the spa back in shape chemistry wise but it looks like heck.
Click to expand...
Can’t really tell anything, your pool logs aren’t showing up to get an idea of what the chemistry has been like.

TFP never recommends dry acid. It adds sulphates to the water which destroy metal and concrete surfaces. Better to use wet acid.
 
BoHpool said:
FC 10
pH purple
TA I added 2 drops of 7 and started adding 8, the sample turned red, I added 2 drops of 9 and it got brighter red and stopped
I used pool math and added half of the baking soda recommended. I waited a few hours and tested pH again. Still purple. I used pool math and added half the recommended dray acid.
Click to expand...
The stains are copper stains.

The pH was below 4.5.

The purple was from the high bromine levels.

People get fooled by the color and think that the pH is high when it is actually too low.

The TA was below 0.

The combination of high bromine and low pH corroded the copper from the heat exchanger.

I would turn the system off and use Jack's #2 to remove the stains and then drain and refill if it is safe to do.

Pools and/or spas can float if drained during high ground water levels.



Copper-Scale-Stuff-5lb-Clean-2-e1563896232209.png


STAIN SOLUTION #2 – The Copper & Scale Stuff | Jacks Magic

jacksmagic.com jacksmagic.com

"Expert" needs help. LOL

Ok, I'm stumped, never seen anything like this before. Here is the pool as I arrived. Opened by homeowner 24 hours ago. Nothing added. CAM00033 by poolmom11, on Flickr PH test came out pale yellow - not even registering. TA test registered nothing. It turned a color I've never seen. FAS DPD...
www.troublefreepool.com www.troublefreepool.com
 
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High levels of bromine can convert phenol red to bromophenol red (dibromophenolsulfonephthalein, whose lowered pKa results in an indicator with a range shifted in the acidic direction – water at pH 6.8 will appear to test at 7.5).

Even higher levels of bromine (>20 ppm) can result in the secondary conversion of bromophenol red to bromophenol blue with an even lower pKa, erroneously giving the impression that the water has an extremely high pH despite being dangerously low.

www.laballey.com

Phenol Red Indicator, 0.02%

Buy Phenol Red Indicator Solution 0.02% w/v | Aqueous Indicator Solution | 500ml Bottle | pH Indicator | For Sale Online | CAS 143-74-8 | Indicator For Cell Cultures | Toxicity | Absorbance | Phenol Red Test
www.laballey.com www.laballey.com
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BoHpool said:
I guess I was hijacking another thread, the moderator moved my post to it's own thread.
This is the thread I was referencing. Anyone else have a never ending tug of war between pH and TA in their spa?
Click to expand...
And you have another thread going on about your spa at....

New plaster now stained

The first 2 pictures are of the new plaster May 28. The last 4 pictures are of the stained plaster yesterday. I followed the TFP new plaster start-up as well as I could. I have a helper who works every other week. I have tried to get him to read and follow directions but he seems immune. I...
www.troublefreepool.com www.troublefreepool.com

What question do you have about pH and TA in your spa?
 
Reduce your pH to 7.6-7.8 and leave your TA alone. Accept whatever TA you get. As long as your pH is stable your TA is fine.
I have been keeping my TA at 80 which I thought was the recommendation of the plaster start-up but now I don't see that.
 
BoHpool said:
I have been keeping my TA at 80 which I thought was the recommendation of the plaster start-up but now I don't see that.
Click to expand...

You are past the 30 day plaster startup so whatever you read no longer applies.

TA of 60 and even 50 is ok. if pH is in the upper 7's and TA is low it is OK. If pH is getting toward 7.0 and Ta is below 50 then adjusting TA up a bit may be required.
 
BoHpool said:
A moderator moved a question I asked from a different thread and made a new thread. Then the moderator realized I had this thread and combined them. Not good moderation in my opinion but here we are.
Click to expand...
Your two problems are intertwined.

It sounds like you have been chasing a false pH reading due to your bromine.
 

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