Procedure to adress Hydration (plaster discoloration)

[handmj]

Our pool is just over a year old. We noticed splotching in our white quartz plaster within a couple months after startup (see attached pics). The pool builder, along with the plaster rep, didn't come out to look at it until 6 months after startup and told us it was hydration. They proposed doing an acid soak. After doing some research, including on TFP, I don't think this is the right approach. We had a company look at our pool, and they recommended draining the pool, acid rinsing and torching to get rid of the moister behind/in the plaster. I've also read on TFP that torching is not recommended, and the splotches can come back after acid wash and torching so I'm not feeling very confident in with this approach either, especially since it will cost $900 + cost to refill pool. I'm also concerned about the torching causing serious damage to the plaster. It seems that if the moister is going to be heated up with a torch, then it could expand into a steam behind the plaster and damage it, unless the plaster is porous enough to allow the steam to escape. However, I'm really not aware of any other solution. Please advise.

Thanks,
Michael

 

[onBalance]

Gray mottling discoloration is not caused by moisture behind the plaster. Think about it, isn't the plaster submerged in water? It is also not caused by "hydration."
"Hydration" is the normal and proper reaction when cement and water are mixed together, which then hardens.
You are correct, any type of "acid rinsing or treatment" or "torching" will only cause damage and shorten the life-span of the plaster finish, including quartz or pebble.

The following post explain the likely causes of the darkening of the white plaster.
How White Pool Plaster Can Turn Gray

 

[onBalance]

Here is another post.

How White Pool Plaster Turns Blotchy

Only by etching the surface severely will remove the graying. I suggest a re-plaster is the only proper way to remedy this problem.

 

[handmj]

New Member with question about solution for hydration

Hello. We had our pool built in May 2017. Within a couple months, our white quartz plaster started having spotchiness, which seems to be hydration. The pool company and plaster company recommended to do a low a low alkalinity soak. After some research on here, I decided against this. We had another company look at our pool, and they also recommended against the acid soak, but instead recommended draining the pool, acid washing and torching the plaster to get rid of the trapped moisture. I've also read on here that torching is not recommended. I'm concerned that this will damage the plaster. However, I don't know of any other solution. Please advise.

Michael

Moved new thread post to existing thread. Marty

 

[handmj]

Thanks for the responses. I've seen several posts about causes of grey mottling and what NOT to do to treat it (acid soak, acid wash, torching), but I have yet to see a solution other than re-plaster. I would hate to spend thousands so soon after building a new pool. Any help would be greatly appreciated.

 

[onBalance]

For many plaster companies, this problem is covered under the warranty. If they can't properly remove the graying, they re-plaster for free.