My pool finally was plastered ~1 month ago. We began to notice what I feared was scaling. Two dark spots near one of the drains and a white swirl spot on one of the infloor heads. Also short white streaks in the shallow areas. The plaster company decided to hit the pool with a large acid dose and it appeared that that the problem was greatly reduced. All white spots in the shallow area disappeared, the white scale around the head was all but gone and the dark areas was greatly reduced as well. He wanted me to keep the LSI slightly negative and continue. Since that time we have had a terrible time keeping the PH down for a few days. Now the TA has gone down to barely 40 and my CH has gone from 290ish to over 400, and this within a few weeks. The discoloration is beginning to return, and although the PH as drifted up greatly a few nights, we add acid and bring it back down immediately each morning. I have been running the infloor system and wonder if the spill over could be contributing to the increase in PH, plus the wind has been relentless.
Anyway I am concerned about the CH increasing so rapidly. The plaster was installed on a very cold day so I suspect calcium chloride was used but not sure if that's the case or how much. I also don't understand how the scale could be reforming since even though we've had PH drift up to near 8 a few nights, it's been brought back down and the drift has been much less the past few nights.
One more note, the pebbelsheen is one of the lightest colors offered, the aggregate all looks grey to me, at least in the shallow areas where it's easy to see, I am not sure if that's just the color of the aggregate or indications of the same problem.
Also I have had a very hard time determining the CH as "endpoint fading" seems to be a problem. We get a slight purple color (very slight) about 31 drops, basically stays that way until over 40 and nothing you could call blue until 45. Assuming that is correct here is todays numbers. (which is basically what it was last night as the PH didn't drift much)