Another scale issue - maybe...

mbeavers1

Active member
Sep 10, 2019
27
Houston, TX
Hi, as we have started getting back in the pool, I have noticed what appears to be some calcium scale but I am almost sure is it efflorescence from the glass tile grout since that is the only place its showing up (see pics). The funny thing is that it's mostly below the water line though the surfaces of some of my glass tiles are very cloudy and I do see some above the water.

Any idea what causes this and how to clean it, especially below the water line? I know its calcium scale cuz it bubbles when I put a 20% muriatic spray on it.

Also, water is pretty balanced using LSI. Right now it is showing 0.01.

PH = 7.6
Alkalinity = 70ish
CH = 330
CYA = 35
Temp = 83F
 

Attachments

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
16,024
Northern NJ
Lower the water and use a diluted acid solution to dissolve the efflorescence.

BTW, your CYA is 40. We round up and if the dot disappears between 40 and 30 you call it 40.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
16,024
Northern NJ
Any idea what is causing this stuff and if it will come back? I dont really want to have to do this repeatedly. Water here is pretty pricey.
There is no permanent fix for it. I think it is partly a problem of the 1" tiles and so much grout lines. The grout is not perfect and there are spider cracks that let water get behind the tiles and then it comes back out as efflorescence. Seems to be a common problem on the tile walls of pools.

Was epoxy grout used?
 

mbeavers1

Active member
Sep 10, 2019
27
Houston, TX
There is no permanent fix for it. I think it is partly a problem of the 1" tiles and so much grout lines. The grout is not perfect and there are spider cracks that let water get behind the tiles and then it comes back out as efflorescence. Seems to be a common problem on the tile walls of pools.

Was epoxy grout used?
I'm not positive but know it was different than the other grout on the water line tile. Will check w PB.
 

JamesW

TFP Expert
Mar 2, 2011
18,419
Do you have a wide shot?

Is there any way that water can be getting behind the wall?

Maybe a plumbing leak in the wall or ground water buildup?