Calcium issues

[Envieddesigns]

Good evening all,
Most of my precast cement copings need to be reset and re-grouted as there are several open joints, on this particular spot there seems to be some calcium build up & water leaching through. As well as the tiles show signs of calcium deposits. The area is not hollow though I’m assuming it’s due to the opened coping and the area of the cement deck above has a crack near the skimmer as well there is one other area that is worst with hollow sounding tile an a small portion of plaster beneath though I can only attach one photo here.

 

[Texas Splash]

Good morning and welcome! You certainly could have some calcium scale if your chemistry levels allowed the "CSI" to remain elevated for an extended period of time. Sometimes we see what appears to be seeping and streaks running out and down from grout lines which in some cases may be efflorescence - moisture from behind. For now, you can try applying a 4/1 mixture of water/muriatic acid and brushing the area. If you need to get more aggressive, a pumice stone may help, but be careful not to scratch the tile. Do test areas first. The links below may give yo more info.

CSI and LSI - Further Reading

www.troublefreepool.com

Pool Care Basics Archives

Your one-stop shop for all things TFP to include: ABCs of Water Chemistry, Recommended Chemicals/Levels, Test Kits, Troubleshooting, and much more!

www.troublefreepool.com

Calcium Hardness - Further Reading

www.troublefreepool.com

 

[Envieddesigns]

Thanks TS, you know what I notice though is during the season the areas don’t have a real issue with it at times I do find like a tiny dot of calcium if it’s calcium under the water on the walls or a small line that forms brushes away easily. But the off season during the winter when the portion of exposed plaster that isn’t under water really calcifies over the months. I always bring my water level below the returns at the end of the season I don’t put my cover on since we don’t have any trees. And by the time the season is about to begin from rain and snow the level is about below bottom of the tile. Is it bad to leave that water that low?

 

[Texas Splash]

I don't think the water level at closing has anything to do with it. Quite the opposite really as I'm surprised that you would see calcium deposits form on those areas when not underwater. Maybe that goes back to the efflorescence? If you feel the need to confirm it's calcium, try to obtain some pieces and pour some acid on it. If they fizzle it confirms calcium. Let's bring a local into the conversation - @ajw22 thoughts?

 

[ajw22]

Hard to say if it is efflorescence or water line scale or a combination of some of both. I see those things along my tile. I write it off to what happens to things sitting outdoors in the elements and haven't tried to figure out all the chemistry.

We have snow and we have various pollution in the air falling on the snow that then gets into the snow melt that runs back into the coping and tile. Just seeing the difference in the colro fo my deck and coping where it is covered for the winter versus uncovered for the winter tells me there is a lot of pollution that comes from the air during the winter.

 

[Envieddesigns]

Hello all,
Circling back on this thread regarding this calcium deposit leaching through what seems like a hairline crack on the wall beneath the skimmers. As you can see from last years photo it’s just constant throughout the year more so during winter and a lot less during the season. Could it be water seeping from above, would this eventually hollow out the wall there? Both skimmers show the same though this one’s more calcified.

 

[ajw22]

The plaster crack under the skimmer mouth indicate you have delamination of the plaster, water getting behind the plaster in the gunite from cracks in the grout around the tile, and efflorescence coming out of the plaster crack. I see cracks in the plaster radiating from the grout lines.

Only a replaster and some grout replacement will fix the root causes.

 

[Envieddesigns]

Oh great. Thanks for the info. 8 years ago I had the replaster done but my grout joints on my copings had cracks that I only repaired last year because I didn’t know as much then, so could’ve been from them 14 years of cracked joints being open/exposed and those same 14 yrs of going to the pool store only once a week or so for my water chemistry. I’ve learned a lot here in my first year at TFP because of all the great members.