Discoloration of Grout Below Water Line

chrisg7

Active member
Aug 28, 2023
41
Dallas TX
Pool Size
12000
Surface
Fiberglass
Chlorine
Liquid Chlorine
IMG_5261.jpegI’ve been noticing a discoloration of the grout around my pool just below the water line between tiles. I’m pretty consistent at keeping the chemicals at the right level and so I wasn’t sure what it might be. The tile was redone only about a year ago, so I’ve been a little disappointing it’s already showing discoloration. But maybe there’s a certain chemical I need to use more of or less of to fix the problem?

Any advice is appreciated!

Thanks!
Chris
 
Wet surfaces always look different then dry surfaces.

Let your water level drop a bit and see if a “discolored” area looks different when it dries out.

I don’t see a problem. The grout underwater looks a bit darker.

Do you brush the pool and tile and grout regularly?

Post a current complete set of water chemistry tests in your PoolMath log.

No, there is not a simple chemical to add.
 
Wet surfaces always look different then dry surfaces.

Let your water level drop a bit and see if a “discolored” area looks different when it dries out.

I don’t see a problem. The grout underwater looks a bit darker.

Do you brush the pool and tile and grout regularly?

Post a current complete set of water chemistry tests in your PoolMath log.

No, there is not a simple chemical to add.
The grout is brown. That’s what alerted me. Yes, I brush once a week including tile.
 
Looking closer I can see the difference in color (brownish vs grey)
How are you currently chlorinating? (Tabs/liquid chlorine/cal hypo)
Are you on a well?
Current Test results would be helpful
Fc
Cc
Ph
Ta
Ch
Cya
You can also try some of these methods to help id your stains/determine if it is actually staining
 
Looking closer I can see the difference in color (brownish vs grey)
How are you currently chlorinating? (Tabs/liquid chlorine/cal hypo)
Are you on a well?
Current Test results would be helpful
Fc
Cc
Ph
Ta
Ch
Cya
You can also try some of these methods to help id your stains/determine if it is actually staining
Thanks for your help!

I currently use liquid chlorine.

I’m not on a well.

I just uploaded a new set of chemical logs.

Let me know what you think — thanks so much!!

Chris
 
Cya is a bit low - How are you measuring a cya of 10?
ta is a dab low too but I doubt that’s the cause of the issue. Still wanna correct those.
Bring ta up to 60 with baking soda before adding any cya as its acidic and will lower ph/ta.
What test kit do you have?

City water can have iron in it as well.
Have you tried any of the tests in the article?
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.