Plaster Questions

CJ7

Active member
Aug 2, 2018
41
Utah
Our plaster was put in on our new pool in June. This issue continues to worsen. I've been using TFP methods since around August.

Curious as to your options of the problem, if it is one and how to fix it.

I do have a constant battle with pH as our water is 7.8 out of the tap and I have a spillover.

IMG_20181027_183153.jpgMVIMG_20181027_183147.jpg
 

kadavis

TFP Guide
In The Industry
Apr 5, 2015
1,645
tucson, arizona
This is what used to be known as spot etching, but is referred now as white spotting. The Onbalance group has done significant studies of this phenomenon and has been the leading authorities outside of the plaster industry on why it occurs
 

Rich D

Bronze Supporter
Aug 3, 2018
960
MA
If I am seeing the pics correctly it is also referred to as Mottling. I have med grey plaster and was plastered in Sept 2017. The plaster looked great going into the winter, However this spring an early summer I had alot of it show up. From what I have read here it is something that just happens to all plaster over time and is just more noticeable in darker colors. I was told by one of the techs that came out my pool looked more like a 3-4 yr old pool instead of a 8 month old pool. As to the cause I believe the study kadavis is referring to concluded it had more to do with application techniques and products used in the plaster then any type of chemical imbalance. However with improper application and products the chemical imbalance will hasten the mottling. This subject is very controversial. However with the research I have done seeing the amount in your pics seems very excessive. I would definitely contact the PB to come have a look. Unfortunately the only "fix" I know of is a acid bath or acid wash, Wich will remove a small amount of the plaster. If done wrong these applications can ruin the plaster. Or leave you with a rough finish. It is also a temporary fix as the mottling will return. It is just a gamble on how long it will take.

Did your PB show you some pools with your color plaster that were a few years old before you made your choice of plaster?
 

Attachments

sktn77a

Gold Supporter
May 16, 2010
1,948
Chapel Hill, NC
Wow, and I thought my pool was bad............. :( In my case, the problem was traced to the plasterer using too much CaCl in the plaster mix (to speed up curing) and dry trowelling the final finish. Of course, the pool renovator and plasterer refused to accept the pool plaster specialist's findings and just blamed my TFP water chemistry.
 

Rich D

Bronze Supporter
Aug 3, 2018
960
MA
Wow, and I thought my pool was bad............. :( In my case, the problem was traced to the plasterer using too much CaCl in the plaster mix (to speed up curing) and dry trowelling the final finish. Of course, the pool renovator and plasterer refused to accept the pool plaster specialist's findings and just blamed my TFP water chemistry.
That is interesting.

What color is your plaster?
Do you have any pics?
How did the plaster specialist determine that? What kind of test did they do ?
 

rccarps2

LifeTime Supporter
Aug 6, 2015
121
PA
Looks exactly like my problem. I detailed it in a few posts, including this one. https://www.troublefreepool.com/thr...Pennsylvania?p=1494127&viewfull=1#post1494127

My plaster is getting replaced this coming spring, under warranty. Took a lot of time working with the PB and Plaster Co., and a tremendous amount of help/consulting from OnBalance to get it resolved.

Neither the PB of Plaster Co. detailed or admitted what caused it, but that it would just be replaced. Going to upgrade to Pebbletec to reduce the chance of this happening again.

I am going to agree with sktn77a, that it is probably too much CaCl and late troweling.

Here is some good reading from OnBalance to help educate yourself when speaking with the PB. http://www.poolhelp.com/home/onbalance-research/

RC
 

sktn77a

Gold Supporter
May 16, 2010
1,948
Chapel Hill, NC
I have plain white plaster. The mottling light grey. Not as bad as yours but disappointing after a new plaster job last year. The plaster guy just knew as soon as he saw the nature and color of the plaster surface (he gave me a couple of scientific papers he's written on this - I looked but couldn't find them). He says it's become so common that plasterers do this so they can finish the job in under a day, start filling, and get their money. There's very little can be done about it - he recommended just living with it rather than knocking a couple of years off the life of the plaster by acid washing.

My start-up was by-the-book, maintaing chemistry and brushing dail for the first month and every other day for the next 3 months. Now I brush once weekly. Chemistry is still where it should be.
 

Rich D

Bronze Supporter
Aug 3, 2018
960
MA
Looks exactly like my problem. I detailed it in a few posts, including this one. https://www.troublefreepool.com/thr...Pennsylvania?p=1494127&viewfull=1#post1494127

My plaster is getting replaced this coming spring, under warranty. Took a lot of time working with the PB and Plaster Co., and a tremendous amount of help/consulting from OnBalance to get it resolved.

RC
Congrats on getting them to fix the issue. If I am reading your other post correctly it seems one of the main reasons (possibly the only one) they agreed to replace the plaster was the overwhelming evidence of the foot prints. I have searched this issue for some time and have not found a instance where the PB agreed to replace plaster for just the "white soft spotting" issue. It seems the best they will do is the acid bath or wash Wich I am not interested in doing. I ended up with just one footprint in deep end However my "white soft spotting" seems to have gotten much worse this summer. The shallower the area the more it seems to be affected. IE the 8' deep end almost seems unaffected.
 

sktn77a

Gold Supporter
May 16, 2010
1,948
Chapel Hill, NC
See this link for an explanation of the spotting problem. White Spotting of New Plaster Pools
Interesting, that's pretty much verbatim what the guy who checked our pool out said - plastering deficiencies. I guess I'm just lucky that it's not too bad and barely visible unless you have an eagle eye! He said we haven't seen continously increasing calcium hardness because it was mild and only a small overall area.
 

Rich D

Bronze Supporter
Aug 3, 2018
960
MA
Interesting, that's pretty much verbatim what the guy who checked our pool out said - plastering deficiencies. I guess I'm just lucky that it's not too bad and barely visible unless you have an eagle eye! He said we haven't seen continously increasing calcium hardness because it was mild and only a small overall area.
Where did you find the "Plaster Professional" ?

Could I ask How much he charged for a consult?

Thanks, Rich.
 

sktn77a

Gold Supporter
May 16, 2010
1,948
Chapel Hill, NC
Where did you find the "Plaster Professional" ?

Could I ask How much he charged for a consult?
Referred by the local pool store. They gave me 3 names, I spoke to each on the phone first. He was the only one that inspired any confidence. He was a formed pool business owner who gave up his business to work for the National Pool and Spa Association before her retired. He charged $100.
 

bmoreswim

Mod Squad
Gold Supporter
Platinum Supporter
LifeTime Supporter
Jul 16, 2012
6,543
Central MD
Pool Size
27000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
I would describe my plaster look as being very similar to yours. Our gray plaster was white marcite tinted with Onyx Diamond Brite. Our "defects" are not the round markings discussed so much as the crackly looking lines and patterns you show. It did also show up after a bit of time (general mottling right away and the crazing look a bit later). And now that we are 5 years in, it has faded though you can still clearly see it. Additionally, I have what I call general mottling though I don't know if it fits the technical description of it. Overall, I've never been opposed to the look as we were told it would definitely not be a flat or even color finish right up front. I've always embraced the look as being unique, and since I didn't feel/don't think it affects the longevity to a large degree - with water quality being much more important overall, I haven't been concerned.

I'm sorry you are having these concerns with your new pool. But I did want to share our experience more as a data point for a similar color plaster and also to share our perspective on the appearance.