Scaling (?) on Tile

[Htown_Mark]

Hey all -- The pool is about 3 months old. Water has been carefully balanced the entire time. Starting to notice this white stuff on the tile in places. This pic attached is the biggest offender, but it is becoming more noticeable in other places. What is interesting though, is that my water line sits below where most of this is occurring. Perhaps this is related to something that wasn't scrubbed off properly from construction?

I've read many threads that speak to multiple ways to address something like this, but this seems different. Any suggestions on the best product/chemical to use and the right brush type?

Recent water results:
FC - 8
PH - 7.5
TA - 80
CH - 400
CYA - 60
Salt - 3200
CSI: -0.19

Thanks

 

[PoolGate]

Have you tried vinegar?

 

[Htown_Mark]

No, I haven't tried anything yet. Figured I would ask before making any obvious mistakes.

 

[generessler]

I have some stuff that looks like this in odd mortar and tile corners of a 16-year-old pool. There is a process called efflorescence where porous mortar wicks water to the surface where it evaporates, leaving calcium behind. I don't know if this is your problem, but the location makes me think it could be. Given the pool is only months old, I believe you should ping the builder. New mortar and grout should not be doing this afaik.

Caveat: I'm not a TFP expert. Just passing along what I've seen in my own learning.

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