No Stains until salt was added

May 23, 2009
12
Denver, Colorado
I have been wandering the sites for awhile.

I have a new plaster pool. I had no stains for the first month waiting for the plaster to cure. As soon as the pool company added salt grey stains started to develop. Solid on the walls and blotchy on the bottom. I did a vit C test and it did lighten the stain. My pool company has said they have never seen a stain like this before and it really isn't their problem. I disagree. The PH was through the roof when they added the salt. Was there some sort of metal reaction. Should I have them acid wash it or should we try the AA method?
 
jfinholm said:
The PH was through the roof when they added the salt. ?
I think this is the reason you got staining and not from the salt. Grayish stains are usually from copper or manganese. Salt is more likely to cause iron staining if salt with yellow prussiate of soda is used (food grade salt) and these stains would be yellow to brown. New plaster startups ususlly include the addition of sequestrant to control any metals and excess calcium.

My question, who is responsible for maintaining the pH in proper range at this time, you or the pool company? That will have a lot to do with who is responsible.

IMHO, the swg is NOT the problem but your water balance is. Fault lies with whomever is responsible at this point in time for maintaining the water balance, IMHO.

Your problem sounds like hydration stains. Sometimes these are covered by your warranty but often they are not. The causes are not known but it is suspected that they may be linked to not enough brushing during start up. Did you do a normal, acid, or bicarbonate start up?

Without actually seeing the stains it's next to impossible to say what they might be but given the facts of new plaster and high pH I would guess hydration stains.
 
Hein lies the problem...when the pool company started filling the pool they added nothing. I was told to brush 2 times a day. No one returned for 2 weeks. when i started getting worried about chemicals I went and purchased a kit. The PH was way off the chart and of course no chlorine. A guy showed up a month later to pour in the salt which was pool grade. When I told him the PH was high he dumped in a gallon of muratic acid and said that new plaster pools always had high PH and it would probably regulate in a month or so. Great...so then I started checking chemicals a little obsessivley. About 2 weeks later the grey stain started. First around the bottom main drain. Then slowly elsewhere. The plaster company showed up and said they had never seen a stain like that before. If it was hydration stains wouldn't they know that? A chemist from the school of mines said that when salt and high PH mix you can get a manganese reaction? I could have that wrong.

bottom line is no one ever told me to add muratic acid to keep the PH down. The guy just showed up and dumped salt in. He didn't test anything.

It does fade with Vit C. Would Vit C fade hydration stains?


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After the Asorbic Acid treatment failed. I now believe that the stains are copper. The pool company says the stains are not hydration stains. Anyway, they are draining the pool on Sunday to perform an acid wash. Wish me luck!

P.S. I had the water tested for copper and it showed 0.2 Is that because the copper already had settled in the plaster?
 
Right, stains are metals on the plaster and not in the water, so they won't show up in a water test. Copper of 0.2 in the water means there is a source of copper, which supports the theory that those are copper stains.
 
jfinholm said:
A chemist from the school of mines said that when salt and high PH mix you can get a manganese reaction? I could have that wrong.
Pure sodium chloride won't cause a stain. I think what he means is that if there are metal impurities in the salt, then these can stain if the concentration of metals or the pH is high.
 
chem geek said:
jfinholm said:
A chemist from the school of mines said that when salt and high PH mix you can get a manganese reaction? I could have that wrong.
Pure sodium chloride won't cause a stain. I think what he means is that if there are metal impurities in the salt, then these can stain if the concentration of metals or the pH is high.
Exactly! High pH is the main factor in determining if there will be staining or scaling in almost 100% of the cases. Second most important factor is temperature.
 

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well....right now it's 82 however, I realize there was a number of mistakes made when the new pool was filled. 1. the pool company didn't adjust the PH (it was super high) and they didn't add a sequestrant before they dumped in the salt at that time the pool was probably 86 - 88. Alas the stains started forming about 5 days after the inital salt dump.

Anyway...the pb is draining and acid washing tomorrow. I just want to make sure the same mistakes are not made again! I do not want to deal with these stains ever again.

any monthly prevention strategies would be most appreciated.
 
any monthly prevention strategies would be most appreciated.
As always, good accurate testing is a key.

Get a good test kit and test for pH daily, FC daily, CC's, CYA, and CH once each week as you're learning your pool. Read up in Pool School what values are acceptable for these parameters.
 
Okay...has anyone heard of this? The pool saga continues.

The acid wash didn't work..They need to replaster the pool. The pool company tells me that after much research, they believe that the stains were cause by PH shock? Which is...the PH was lowered too quickly, too much muratic acid was added at once and it damaged (stained) the plaster? Has anyone experience this?
 
Who was your pool builder? I had the "hydration stains" as indicated in my pics, the acid wash worked to get rid of them, however, they are now returning. Thats cool that your PB is going to re-plaster, it should have been a warranty issue in my opinion. As far as too fast of a PH drop, Im not familiar with the properties of plaster or marcite to provide you with a factual answer. All I know is that Ive been batteling my stain issue for most of my pools existance (8 months) and will be meeting with the warranty rep. friday to see what the next solution will be.
 
Colorado Pool Systems was the builder. The acid wash did nothing! I'm sorry your stains came back. It is very frustrating when many professionals can not tell what the stains are from.

Many plaster companies came and looked at the stains, only one company had this happen to them... 15 years ago! They ended up replastering.

I'm not looking forward to the whole new pool start up process again! However, I have learned a lot.
 
Trust me I feel your pain. I have had my pool replastered already once since it was built 8 months ago for odd blue swirls in the plaster. Now Im probably looking at a second plaster job. This time Im going to request reimbursement for water and pool chemicals. I didnt the first two refills, but enough is enough. I have tried to deal with the warranty dept. to put in a pebble tech product instead of plaster due to all of the issues. However, they were gonna charge $5,300. We may have to take this to civil court :cry:

I agree, its frustrating when no one can accurately figure out what the stains are. I hope all turns out well with your replaster. Let us know. :cop:
 
yes, when we drained the pool to acid wash we negotiated that they pay for water and chemicals. It seems that our pool company has no knowledge of chemicals and how much work it takes to get water properly balanced again. They will be paying for water and chemicals again trust me!
 
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