Quote Originally Posted by AprilRose View Post
We have a 16,000 gal, saltwater pool. It was finished in Sept. 2004. We have the 3M Colorquartz in our plaster. The last four months or so we have noticed that the flat surfaces (seats, steps) are getting very rough to the point of us not wanting to even use the spa (too cold for the pool right now). I did a search here and saw that others have had this problem but did not see what the ultimate solutions were. Can anyone offer some advice? I tried using the metal tile brush on it but no luck with that. We tested today, here are our numbers:

FC-6
CC-0
TC-6
pH-8.2
Alk-180
Cal-380
Cya-30
Temp-60
At first glance, it looks like your Ph & Alk are too high and with a CH of 380, it is likely that you are having some scaling conditions. Also, with a PH of 8.2, your SWG is unlikely to work very well. So the first order of business is to drop your PH down to 7.2 - 7.4. This should drop your alk some as well but you may need to work on that too with aeration and acid.

As for making the surface smooth again, that may require an acid wash. I would check with your plaster installer to see if they have any suggestions.