Paint a pool, how to get rid of what I am guessing is mineral growth

[cmb1998]

Hello,

I bought a house with an in ground pool. It's a fairly sizable pool, 3ft deep to 8ft deep, about 40 by 30 but roundish. The pool was build in the mid 80's, it was originally a troweled finish of some sort and then painted and all the equipment replaced in the mid to late 2000's.

The paint is peeling, and there are several spots where I have this this hard white growth that looks like a mineral growth. It's scattered around the pool in several spots. Other than this, the pool surface is in really good shape.

What is the growth stuff? How do I get rid of it to prep for paint? (I understand there is substantial work to prep for paint, clean, acid wash, test for paint type, check moisture - it's just the white growth that is throwing me off).

I'm fairly handy, built several houses from the ground up, but never played with pools. Appreciate the help.

Thanks,

Chris

 

[JoyfulNoise]

Sounds like possible calcium scale, but hard to know. Scrape some of it off into a shot glass and put of few drops of muriatic acid on it. If it fizzles, it's some kind of calcium scale.

You'll find little approval on this forum in using paint as pool surface. Even the best types of "pool paints" are pretty low quality and will only last a few years before problems creep in. Normally an in-ground, concrete shell pool would either have been plastered or set with a vinyl liner. Your situation makes me think that the original owner did not want to fork over the money for a new re-plaster job and just simply covered over the old surface with paint. As you can see, it's not a very good long term solution.

What's your budget? The right way to redo the pool surface would be to get it professionally replastered. But that's a lot of money ($8k to $10k easily depending on your location).

 

[cmb1998]

I agree paint isn't the best option. I did get two quotes on re-plastering and it was 12K and 14K. I think I can paint it for under a 1K. We just bought the house, and this is a 2 - 3 year band aid to put money into other projects until we have an idea of what we want to do with the pool. Since it was already painted, don't think I am really moving in the wrong direction.

The growth looks like calcium. If I confirm, what is the best method to get rid of it? Can I just target the areas with heavier muriatic acid and then paint over? What causes that?

Sounds like possible calcium scale, but hard to know. Scrape some of it off into a shot glass and put of few drops of muriatic acid on it. If it fizzles, it's some kind of calcium scale.

You'll find little approval on this forum in using paint as pool surface. Even the best types of "pool paints" are pretty low quality and will only last a few years before problems creep in. Normally an in-ground, concrete shell pool would either have been plastered or set with a vinyl liner. Your situation makes me think that the original owner did not want to fork over the money for a new re-plaster job and just simply covered over the old surface with paint. As you can see, it's not a very good long term solution.

What's your budget? The right way to redo the pool surface would be to get it professionally replastered. But that's a lot of money ($8k to $10k easily depending on your location).

 

[JoyfulNoise]

I agree paint isn't the best option. I did get two quotes on re-plastering and it was 12K and 14K. I think I can paint it for under a 1K. We just bought the house, and this is a 2 - 3 year band aid to put money into other projects until we have an idea of what we want to do with the pool. Since it was already painted, don't think I am really moving in the wrong direction.

The growth looks like calcium. If I confirm, what is the best method to get rid of it? Can I just target the areas with heavier muriatic acid and then paint over? What causes that?

OK, that makes sense. I am by no means an expert in pool resurfacing but my guess is you're going to want to power wash off all of the old paint using a good, high-pressure power washer and then you're basically going to want to mechanically scrap away any remaining paint and calcium spots until you get down to a "virgin" plaster surface. You'll then want to repair any cracks in the plaster and check to make sure all of your intrusions through the shell (return lines, light fixtures, etc) are all nice and well sealed. Then acid wash and paint with the best available paint you can find. I believe pool paints are epoxy-based as you want something that is going to bond to the plaster layer.

When it comes time in a couple of years to replaster the pool, you might look into AquaBright by ecoFinish. It's propane torch flame sprayed thermoset polymer that is designed to be applied over plaster. It gives you all the chemical benefits of a vinyl type surface (no chemical interaction with the water) but all the mechanical strength, texture and colors of a high quality plaster surface. The installation cost for a resurfacing job is very competitive with standard re-plastering (or so I'm told by the one TFP expert on the forum who installs AquaBright coatings in California). The parent company (ecoFinish) is out of Pennsylvania but it looks like they have one installer so far in Canada all the way out in Ontario (I know, it's no where near you). But, perhaps in the future, they will have expanded to your area....

 

[JamesW]

If the paint is peeling, it might be best to sandblast it all off. The scale might be scale from high CSI or maybe calcium nodules from cracks in the plaster. If it’s nodules, you likely have delaminating plaster.

For delaminating plaster, the best thing is to remove the plaster and replaster.

Be aware that paint will begin to chalk almost immediately, in most cases. That means cloudy water from paint dissolving almost constantly.

Can you post test results of your water?

Can you post pictures of the scale?

 

[kimkats]

I see where you are coming from. Do what you can to patch it together until the funds find their way to your pockets!

Once you get the surface where you want it please make sure to get a good test kit to keep control of your water.

Let us know what you decide to do.

Kim

 

[blazeone]

Have you considered an epoxy finish. See the thread called "over my head in Wisconsin.

 

[cmb1998]

That is a really long post...

I am leaning towards Epoxy, probably a high build two part. I am guessing that's what on there now, but don't have any way to confirm and would do a bonding / primer coat.

Are there ratings as to what paints are better anywhere? In looking across the web there are many manufactures all say their are best. Any tests anywhere?

 

[kimkats]

You will not find any paint tests here at TFP but there are a few threads like the one they pointed out that talks about painting a pool. The search box at the top of the page may be your best bet to see what people have done and used in real life. There are not many though.

Kim