White Splotchy Areas

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J

Jabooh1

0
Jan 7, 2013
320
Friendswood, TX
Hey everyone. Found this white splotchy areas in my blue-ish pool today.
This is the best pic. On a bench under my waterfall.


On a step between horizontal and vertical parts.


The areas are not any rougher than the pool and seem to be in areas in corners or vertical to horizontal changes.

Current test data:
FC 2
Cc 0
Ta 80
Ch 350
Oh 7.9 (added acid
Cya 60 (+25 oz of stabilizer then I ran out)
Temp 80

Thoughts?

I tried searching for white spots on pool but can't find anything definitive.
 
I think they are cream spots. Meaning Imperfection in the application of your finish. Those is usually adressed through trowelling, but some finishers take care of it with acid washing, scrubbing, and pressure spraying. Sometimes there are still these small spots are left behind. Some can be reduced with brushing to differing degrees, some will remain.
 
No, this happened during installation of the plaster. It's the plaster material/cement paste that holds everything together, and it should have been removed, or better yet, not let happen during the application process. Be prepared, and keep it under your hat until (if) he says it, but builders and installers love blaming things wrong with plaster on "bad water chemistry". Most problems of appearance are associated with install versus water chemistry more often than not. I have more of these than I wish in my pool, and there would have been more/worse ones had I not made them address them on install day.
 
I didn't notice them at first. Looks like they are just showing up.

The PB started with "make sure to not get grass fertilizer in the pool." I have fertilized since the pool. Then he shifted to "is it where shock could have accumulated and bleached the color out". I have added shock. Ever.

He sent photos to the plaster guys.
 
Received a call from the pool plaster sub (not he PB). He was very helpful. He indicated that he tested it and it turned out to be calcium deposits. He tested the water and the PH was 8.1. When I tested it yesterday it was 7.5. That is a 0.6 clime in less than 24 hours? Going to test right when I get home.

He also indicated keeping the PH at 7.2 and that will (over time) eliminate the small amount of calcium build up I have. Now if I do that it drops my CSI a lot! Is this safe?
 
I doubt that the white areas are calcium scale deposits.
I would advise not making the water more aggressive with a low pH. Better to keep it balanced.

If the white "stained" areas are small, I would try using 100 grit wet-or-dry sandpaper to see if they come off.
If the white disappears quickly, then perhaps it is a calcium scale problem, which would come off easily on new plaster pools.
But if it requires a whole lot of sanding, then it is more likely caused by improper wet troweling.

Improper wet troweling does not show up immediately while or soon after troweling is completed. It takes a couple of months to show up (depending on the degree of abuse), which is why this problem is often blamed on supposedly bad water chemistry balance. Improper wet troweling causes the surface (where troweled with water) to become weak and porous, and over time more porosity develops and loses it's (plaster) color and turn whitish.
 
Sorry, but I have my doubts about it being scale.

It may or may not help a lot, but 7.2 isn't going to hurt you. It's likely going to be more effort than you are used too. Your pH will want to come back up. If you keep doing this down to 7.2, watch the TA so that you don't crush it. You may be ok with your makeup water putting some back in, just be mindful of it.
 

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So the plaster guy had a bucket of Copper and Scale remover (or something like that) that was a powder. He added a handful on one step and it bubbled for a minute. He then brushed it away and it looks like this...


Now this is a different area than the pictures above, but there seems to be a scale issue I was unaware of.

The plaster guy said to add a sequestering agent to keep the calcium suspended and the filter get it.

Here are test results from yesterday.
Fc 3
Cc 0
Ta 70
Ch 300
Salt 3000
7.8
Cya 65
 
It looks like the plaster guy etched the plaster surface. Nothing more.
Did he try that process on the white areas and spots?
If not, the question is why not? He didn't prove that the problem is calcium scaling.
 
The etching treatment does remove some of the cement and will darken colored pigmented plaster.
I suggest you ask him to come back and do that same "acid" treatment on the white areas.
If the white areas are calcium spots, then the acid treatment will remove the white spots quickly and easily.
If it doesn't, then the white areas are not calcium scale, and instead they are "porous" spots that lost the color. That is opposite of calcium scaling.
Ask him to bring some sandpaper to try. Sanding will probably make the other plaster areas also turn slightly darker.
 
Most dark color plaster pools will have a slightly lighter shade of color uniformly and throughout the entire pool, and whenever a think layer of the surface is removed by acid or sanding, one will generally notice a difference in the color. That is not indicating bad water chemistry.

So what about the white areas that you originally took pictures of?
Did you sand those areas? Can you remove those white areas? That appears to be the main issue.
 

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