Crazy amount of scale showed up after Elsa!

[RogerThat]

Never been anywhere near this bad. I did super shock the pool after the storm because a lot of runoff water got in. Within a day or two it showed up bad. My test strips show everything in normal but, this is just crazy. I did spray a diluted MA solution on it and it did fizz. It removed a lot of it but, the scale is now coming out of the grout in places It's never been before. All I have a basic test strips. Any idea on what I should do?

 

[JoyfulNoise]

How high up is your water table and is there a lot of water saturated ground around your pool?

 

[RogerThat]

The water table is very high. We had major flooding around here even before the tropical storm. The water has nowhere to go. My grass is mushy to the point we can barely walk on it.

 

[JoyfulNoise]

Then what you’re seeing is efflorescence. The concrete shell of your pool is literally acting like a wick, sucking up ground water, and then oozing out through your grout. As the water travels through your concrete is becomes highly mineralized and the pH goes way up. When it exits through the grout it evaporates and leaves all that scale behind.

Not much you can do just until the water subsides.

 

[RogerThat]

Interesting. My PH is good though. AND this type of floding in not uncommon around here but, this is the first I've ever seen it like this. The other thing is that as per my pic, the worst area in in the spillover from my raised spa into my pool. It is not pulling water from the ground. I appreciate the reply but, I just don't see how that can be happening since the spillover is far from the ground water. I'm happy to be corrected though if you can explain that part.

 

[JoyfulNoise]

Interesting. My PH is good though. AND this type of floding in not uncommon around here but, this is the first I've ever seen it like this. The other thing is that as per my pic, the worst area in in the spillover from my raised spa into my pool. It is not pulling water from the ground. I appreciate the reply but, I just don't see how that can be happening since the spillover is far from the ground water. I'm happy to be corrected though if you can explain that part.

It's pretty simple actually. You're pool is a giant concrete shell buried in the ground (I'm assuming it's a gunite pool because you have no signature information). Concrete is NOT water tight. So think of it like an unglazed clay pot submerged in a sink full of water (your ground is saturated with water right now) - the clay pot will absorb water. Your concrete shell is like the clay pot, it is absorbing water all the time. Due to it's porosity and capillary forces, the water will move through the shell looking for any exit point it can. The plaster coating your pool surface is hydraulically sealed, so no water can penetrate the plaster. Your ceramic tile is hydraulically sealed as well. The grout in between the tile, on the other hand, is not hydraulically sealed. So, as the water moves through your shell looking for an exit point, your grout is the perfect spot for it. Now a lot of pools are constructed with a water barrier material coated behind the tile to reduce the penetration of water into the shell. That coating can get compromised over time and some pool builders neglect to do a good job of coating the waterline and all spa surfaces. Spillways are often neglected. Without a barrier layer, water moving through the shell will make it out through the grout. The water that gets absorbed by the concrete and comes out through the grout absorbs calcium from the cement as well as increases in pH. When it hits the air, it evaporates and leaves behind all those minerals and scale it absorbed along the way. This is how efflorescence works. It's quite common in cement structures and you see it all the time in concrete bridges that are near bodies of water.

 

[an1vrsy]

Obviously, I’m not the OP, but kudos Matt for that explanation. Now, I understand how/why efflorescence happens.

 

[RogerThat]

Thank you very much for that explanation. So, you said I just have to wait until the water levels go down. When that happens, what can I do? Will it just go away on it's own or should I apply more MA?

 

[JoyfulNoise]

I would suggest you clean it off regularly and not let it build up. The thicker the scale becomes the harder it is to remove and it will eventually start to incorporate dirt and dust and look very unsightly. As often as you are comfortable with, use diluted muriatic acid to clean it off. It could take a long time for it to stop so you might consider having the time grout sealed to help reduce its occurrence.

 

[RogerThat]

Thank you Sir for the info and advice!

 

[Romoth]

I had efflorescence on my spillway and a combination of a lot more care around CSI and making them come out and re-tile the top of it (had hollow spots) has really reduced it. It still happens, but it's a lot more minor. Thanks for the explanation. That helped me too in understanding it! Our PB definitely did not seal the spillway...