Calcium on spillover/wall

fsworld

Member
Dec 9, 2017
6
Atlanta
Hopefully this is the right place for this. My pool is 2 years old and we have been constantly fighting this battle. It mainly builds up on the grout lines where the spillover is but as you can see it leaches onto the tile and ultimately happens everywhere. Our calcium runs around 200 as my thought was to keep it on the low side to minimize the build up.

The questions...
1 - Is there anything with the water chemistry that we can do to minimize it?
2 - Is there something we could do to the grout to minimize it? Is it actually the calcium leaching out of the grout that's causing it?
3 - Is there a way to remove it? I have literally tried everything from baking soda blasting to calcium removers to acid. Ultimately its better but comes right back and where I have really forced to get it all clean, I've messed up the tile.
 

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mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
23,001
Laughlin, NV
Welcome to the forum.
I suspect that is efflorescence.
Be wary of keeping your CH too low. That can harm the plaster in your pool.
Can you post a full set of test results?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
11,701
Northern NJ
You likely have some water getting into your spa wall and pushing out salts from the gunite that create the efflorescence. The root cause is water getting into that wall. The difficult task is finding how the water is getting in.

Efflorescence is not a water chemistry problem and the CH level in your pool will not change the efflorescence. The minerals that you see leach from the wall, not your pool water.


 

fsworld

Member
Dec 9, 2017
6
Atlanta
I will do a water test today and report back. What do you all recommend for the calcium? As I said, I was keeping it on the low side of 200-400 which is what the pool company said to do. Its a salt water pool with gunite/pebbletech and is almost 2 years old.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
16,116
Tucson, AZ
Based on what you saw during the pool build, did the pool builder or tile installer apply a waterproofing barrier (would look like a painted layer on the gunite wall before tile was set) to both sides of the spa wall?
 

fsworld

Member
Dec 9, 2017
6
Atlanta
Based on what you saw during the pool build, did the pool builder or tile installer apply a waterproofing barrier (would look like a painted layer on the gunite wall before tile was set) to both sides of the spa wall?
Negative. I asked about it and the response I got was it was not needed. That said the painted concrete wall above the pool wall is waterproofed on the back side.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
16,116
Tucson, AZ
Negative. I asked about it and the response I got was it was not needed. That said the painted concrete wall above the pool wall is waterproofed on the back side.
His opinion is contrary to construction best practices. Anytime you have a raised wall holding a body of water, water-proofing (both on the positive and negative side) is critical. That wall should have been waterproofed both inside and out.

What you’re seeing is efflorescence from water saturating the the cementitious materials and then, when the water is not flowing, the areas dry out and minerals get drawn to the surface leaving the crust behind that you see. A properly waterproofed wall and the use of epoxy grout (non-cement based tile grout) would likely eliminate the issue all together.

Water chemistry changes will not help.
 
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fsworld

Member
Dec 9, 2017
6
Atlanta
Alright I attempted to update my signature with all of the info! As for my readings, here they are...

Free Chlorine - 2.5
Total Chlorine - 2.5
Combined Chlorine - 0
pH - 7.8
Hardness - 205
Alkalinity - 81
Cyanuric Acid - 100
Copper - 0
Iron - 0
Phosphate - 459
 

fsworld

Member
Dec 9, 2017
6
Atlanta
His opinion is contrary to construction best practices. Anytime you have a raised wall holding a body of water, water-proofing (both on the positive and negative side) is critical. That wall should have been waterproofed both inside and out.

What you’re seeing is efflorescence from water saturating the the cementitious materials and then, when the water is not flowing, the areas dry out and minerals get drawn to the surface leaving the crust behind that you see. A properly waterproofed wall and the use of epoxy grout (non-cement based tile grout) would likely eliminate the issue all together.

Water chemistry changes will not help.
Unfortunately and not surprisingly, he disagrees. That said, do you all think there would be any help if i took out the grout and replaced it with epoxy grout or would it be a wasted task? I really don't want to have to redo the tile and definitely not the pebbletec inside the hot tub.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
16,116
Tucson, AZ
Unfortunately and not surprisingly, he disagrees. That said, do you all think there would be any help if i took out the grout and replaced it with epoxy grout or would it be a wasted task? I really don't want to have to redo the tile and definitely not the pebbletec inside the hot tub.
Yep, you can never argue with a pool builder - all of them think they’re the god’s gift to the construction world and that they all know everything there is to know about pools. Most of them just simply know to build the pool “they know” and, when you add on design features they don’t understand, their ignorance shows. I can’t tell you how many times TFP gets threads about spillover and negative edge spas with efflorescence problems and, 9 times out of 10, when you ask if proper waterproofing was done, the answer is usually no. Then, because no PB wants to admit fault and cause themselves a warranty issue, they blow it off and tell you that “no one does what your reading about” or “what do those kids on the Internet know...”. It’s sad.

Anyway, Epoxy grout would certainly mitigate the formation of efflorescence on and through the grout surface but it would require chipping out the old grout and apply the epoxy grout. Epoxy grout isn’t fun to work with and requires someone who knows what their doing so I would not trust the PB to get it right. You may still get some efflorescence but it will be less.

Another option is to clean the tile and grout really well, let it dry as much as possible and then apply a grout sealer. It won’t last forever so you’ll be doing over again, but it may help. You could test it out on a small area to see if a standard sealer would work and what color change might happen to the grout.
 

JamesW

TFP Expert
Mar 2, 2011
16,978
Unfortunately and not surprisingly, he disagrees.
If it was a water chemistry issue, the scale would be much more uniform.

The fact that it's only on the grout and only in specific spots indicates efflorescence as previously indicated.
 

Flying Tivo

Well-known member
Jan 24, 2017
1,136
Monterrey, NL, Mexico
You can stop using your spillway, clean the efflorecence and if it comes back, you probably have water leak on the spa side. If not then its the water from the spillway itself and then an epoxy grout will probably save the day.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
16,116
Tucson, AZ
Efflorescence is a cyclical water saturation phenomenon and does not necessarily indicate a leak. If you think of cementitious and stone surfaces as porous materials that act like a sponge, then efflorescence occurs because the material saturates with water that has low saturation of minerals. The water comes into contact with the materials in the grout and wall and becomes oversaturated with minerals. Once the water source stops, the surface quickly dries and all the water built up in the material begins to migrate to the surface. As it evaporates it leaves behind all of the absorbed minerals which build up as a granular and spongy scale. Unlike pure calcium scale, efflorescence can contain carbonates, silicates and even chloride and sulfate salts. Efflorescence with be slightly etched by acid while pure calcium scale (calcium carbonate) vigorously bubbles when exposed to acids.

The purpose of using waterproofing layers is to mitigate the size of the “sponge” so that water flowing on a surface really has no where to penetrate. Epoxy grout will help to seal up the “sponge” as the ceramic tiles are impervious to moisture. But, it will take quite a bit of work to regrout those tiles and the cost is non-trivial.
 

fsworld

Member
Dec 9, 2017
6
Atlanta
I guess the question is.... If its driving us crazy and we want to address it, would it be best to regrout with epoxy or just rip off all of the tile and waterproof, retile, and grout with epoxy. I can't imagine its worth it to also waterproof the spa side and re pebbletec at this point.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
11,701
Northern NJ
I guess the question is.... If its driving us crazy and we want to address it, would it be best to regrout with epoxy or just rip off all of the tile and waterproof, retile, and grout with epoxy. I can't imagine its worth it to also waterproof the spa side and re pebbletec at this point.
I don’t think you will totally fixed it until you address the root cause. Water is getting into that wall and it should not. That water has to go someplace. Wherever the water goes will not get good for your pool or deck.

Water and nature always wins. Just look at the Grand Canyon.

Right now the water has an exit on the tile although it becomes unsightly. The water will find an exit.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
16,116
Tucson, AZ
I guess the question is.... If its driving us crazy and we want to address it, would it be best to regrout with epoxy or just rip off all of the tile and waterproof, retile, and grout with epoxy. I can't imagine its worth it to also waterproof the spa side and re pebbletec at this point.
Well, at the end of the day it's your pool and you gotta do what brings you peace of mind but you also can't drive yourself nuts chasing after perfection. My suggestion would be to start off with the path of least resistance - find a good quality grout sealer and apply it to see if it holds back the efflorescence. Sealing the grout will mean doing a thorough clean up job on the tile (scrubbing the scale away and exposing a fresh grout layer). I have used Lysol Advanced Toilet Cleaner (the kind that is 10% hydrochloric acid and thickeners) and a stiff nylon brush to scrub away grout efflorescence. It can be done in a very controlled manner and allow you to target the grout with minimal over application. It's also something that can be done while there is water in the pool and requires no draining. The other alternative is to use a pumice stone but that can scratch tile OR to buy an industrial cleaner like Bio-Dex 300 but that requires proper PPE's as you must be very careful with that chemical (it contains a small amount of hydrofluoric acid which is very dangerous). Once you get the grout and tile cleaned to your satisfaction, then I would try the grout sealer. Again, it's probably something that can be applied with minimal effort and only lowering the water level to the bottom of the tile.

If the grout sealer works out well, then it's a simple fix. If not, then you can start searching for a tile company that would be willing to come in and redo the grout. Chipping out grout always risks tile damage so you'd better have spare tile on hand if something gets cracked. If the tiling contractor knows the difference between epoxy and cement grout, then they're likely able to do a decent job. However, expect that much work to cost you some serious coin and they will likely not schedule your job until they have some downtime in their workload.

Finally, if all else fails, you can call in a pool remodeling company and get pricing on ripping out the tile, sealing the wall and then resetting new tile. That's a huge job that will require the pool to be drained and you run a very high risk of the plaster getting chipped and cracked so it's not a very reasonable solution unless you intend to replanted as well.
 

RoyR

Bronze Supporter
Jul 31, 2018
265
Escondido/CA
The spa wall had to be waterproofed inside / outside with an elastomeric waterproofing membrane (before tile / plaster) for exactly this reason.. that calcium is coming out of the spa wall cement.
 

kimkats

Mod Squad
LifeTime Supporter
Jul 10, 2012
42,519
Tallahassee, FL
I have such a big sad for you :( That is such a pretty pool/spa!!! I love the tile you picked! I hope you find a way to fix this problem long term. You have been given some wonderful help. These guys really know their stuff so you can take what they say to do to the bank. Please let us know what you do and what materials you use so we can learn from you along the way.