Question on pool plaster discoloring

[BTERRY1]

Hi all. First time poster. A year and a half ago we had our pool redone. New plaster, coping, and salt systems added. We wanted dark as possible plaster. Pool guy told us it will get modeled looking over time. Does this little normal? I tried brushing and scrubbing but nothing will remove it. PH is kept at 7.4. Alkalinity at 80ppm. Thoughts? Thanks in advance.

 

[ajw22]

Welcome to TFP.

That is within normal color variations for a dark colored plaster.

 

[LaROckl]

Yup... I did a redo as you did ...coping, plaster, salt system etc. I even had *all* the old plaster removed down to the gunite. This was 4 months ago... and while *very*, *very* slight (barely noticeable) ...it has begun to mottle. I do not brush/scrub... just the wheeled pool cleaner. I visited about a half dozen *dark* pools in the neighborhood that had been done from 1 to 7 years or so and saw the mottling over time. In the natural world it's all mottled. Personally, I don't mind the mottling at all... looks like Costa Rica shore line. My understanding is that the calcium from the plaster will continually bleed through as it cures... it will slow over time ...but, it will never stop. <-- correct me if I'm wrong here.

 

[Rich D]

I only wish my 2 yr old med Grey plaster looked as good as that. I do not mind the mottling but my pool looks like it is going to quickly turn into a off white plaster finish and a lot of the mottling looks like trowel marks instead of random color variations, along with a few foot prints...

 

[LaROckl]

Y'all got some sweet pools! Anyone considering a *dark* pool should check out a few in your neighborhood that are 4 to 7 years old and decide from there. In my case the mottling didn't bother me. However, I do prefer the white plaster (the wife wanted the dark) the light refraction is different i.e., white plaster = Caribbean green tint, grey plaster = blue tint. I also think that the white plaster was a better match for our period 50(s) - 60(s) retro motif.

I'll put up some pics of mine once the neighbors GET OUT OF THE POOL ... I'm hiding up in my Lionel Train Room at the moment.

 

[BTERRY1]

Thank you all for the follow up. I was worried something might be wrong. All’s good. Thx!!

 

[SteelBlue]

Sorry but none of the above pics are "normal" for a dark colored pool. Go around and look at some model homes, most will have dark colors these days, and none of them look like that. If a pool company can make a model home's dark pool look good, then someone else can too. My pool was redone six weeks ago with a dark plaster/pebble. It has very faint mottling, a cloudy white dusty look to the bottom. It is nowhere near as bad as those shown above, and my installer agrees it is not good. But he says wait three months for everything to cure and if it's still the same, he will remedy it. How? I don't know, but I bet it will be an acid wash.

 

[ajw22]

Diagnosing Pool Plaster Problems

Plaster Discolorations – New white pool plaster can discolor (darken or turn gray) from adding excessive calcium chloride set accelerator, from late hard troweling, from thin and thick areas due to an uneven shell, etc. Gray (or grey) mottled discoloration (also known as “water entrapment” or...

www.troublefreepool.com

 

[BTERRY1]

it's me again. reviving this old thread to talk through possible options? The Pool has continued to get more modeled. As much as I hate to say it, I am beginning to hate my pool. New pictures attached. Today I took my stainless steel brush and got aggressive in a couple spots and it seemed to take away some of the white edges. Like they where deposits. I am sure I had a part to play after start up, but I am asking if there is anything i can do now to make it less noticeable? I am willing to try anything short of re-plastering. I do not want that expense. Acid wash? Scale remover?

Current water perimeters are as follows.
FC 4.5
PH 7.6
TA 70
CH 450
CYA currently 60. working on bringing it up to 70
CSI -.22

thanks in advance

 

[ajw22]

@onBalance what do you think?

 

[onBalance]

The severe white discoloration in this pool appear to be caused by improper plastering workmanship. I don't consider this normal mottling.
An acid treatment is not going to effectively remove the white spots and streaks. The appropriate to remedy this is to power sand and polish the entire pool. It will take a lot of sanding, and IMO, the plaster contractor should perform that work for free.

See these posts: They are applicable to this situation.

White Spotting of New Plaster Pools

The problem of plaster spotting has been an ongoing puzzle and controversy in the swimming pool industry for over three decades. The generally round, smooth-yet-unsightly white soft spots in new plaster pools have long been a source of contention among pool plasterers, and pool chemical service...

www.troublefreepool.com

The Art of Good Pool Plaster Color

An attractive plaster color (other than white) is often preferred by pool owners. However, it is very difficult for plasterers to produce a uniform and consistent color. The reality is that there will always be some minor shading (mottling) and variation in the color and can never be uniform...

www.troublefreepool.com

 

[BTERRY1]

The severe white discoloration in this pool appear to be caused by improper plastering workmanship. I don't consider this normal mottling.
An acid treatment is not going to effectively remove the white spots and streaks. The appropriate to remedy this is to power sand and polish the entire pool. It will take a lot of sanding, and IMO, the plaster contractor should perform that work for free.

@onBalance - thank you for the reply. so i assume trying to go with a calcium build up type removal will do nothing either? i will reach out to the plaster contractor and see. it has been a little over 2 years, so i can only imagine it will go nowhere but we shall see. any chance you can give me an idea of exactly what they did wrong so when I talk to him i could give him some specifics? thanks again.

 

[onBalance]

The white spots are not a calcium build up type problem. It is just the opposite, it is due to a loss of calcium and color pigment from the plaster surface and resulting in porosity. A porous surface naturally becomes very light in color, even to the point of being white. Based on plaster studies with this type of problem indicates that water was added to the surface while troweling, and that a fast hardening agent (calcium chloride) was also added to the plaster mix. Those two issues result in a porous surface which allows pool water to penetrate the surface and naturally dissolve those two plaster components out of the plaster, and the porosity becomes more severe. That whitening process can take a few months or more to develop the whiteness.
What are your current water test readings?

 

[BTERRY1]

What are your current water test readings?
[/QUOTE]

Current water perimeters are as follows.
FC 4.5
PH 7.6
TA 70
CH 450
CYA currently 60. working on bringing it up to 70
CSI -.22

thank you for the detailed information.

 

[onBalance]

A couple of things to share with the plaster contractor.
Color pigments manufacturer companies warn against the adding of calcium chloride to the plaster mix that contain color pigments as it will cause blotchiness. The Portland Cement Association warns against water troweling as it also causes blotchiness.
An analysis of the plaster can be performed to determine the amount of calcium chloride added.
Your water balance looks good. And don't allow the pH to be lower than 7.6. Good luck, and push hard.

 

[BTERRY1]

A couple of more things to share with the plaster contractor.
Color pigments manufacturer companies warn against the adding of calcium chloride to the plaster mix that contain color pigments as it will cause blotchiness. The Portland Cement Association warns against water troweling as it also causes blotchiness.
An analysis of the plaster can be performed to determine the amount of calcium chloride added.
Your water balance looks good. And don't allow the pH to be lower than 7.6. Good luck, and push hard.

@onBalance - you rock! thank you.

 

[SteelBlue]

I think you are going to need a replaster under warranty. It looks terrible and the contractor could not disagree.

 

[BTERRY1]

I sent pictures to the contractor and he finally got back to me. He feels based on the pictures that it is calcium build up related. According to him, "this is quite common on all plaster pools and just more visible on darker surfaces and will be contacting me to discuss". I have not met with him yet or told him the research and learning i have found here. I felt best to start slow, and not put him on the defensive to quick. Since he did the work, I will follow his recommendation and then take it to the next level if i have to to ensure that i eventually get the pool i paid for. i will keep everyone posted.

 

[ajw22]

Typical contractor initial response.

 

[Rich D]

Typical contractor initial response.

Yup.. Soon to be followed by the inevitable "acid wash/bath" suggestion that will most likely give you a rougher surface and will definitely remove a layer of plaster thereby shortening the life of the plaster and any restored color will not last long...