In the last couple of weeks I've noticed some splotches on the bottom of my pool--mainly on some of the steps and in the shallow end. They could have been there longer or just not as noticable. Please see the attached photo. It's the lighter colored sort of round marks. They don't come off with a steel brush and they seem to be in the plaster itself. I know that it's common for Luna Quartz to have imperfections and perhaps that's all this is. The Luna Quartz is still young--about six months old. I'm still adding about a gallon of MA each week to keep the pH in the 7.5 range. The water is very clear and blue. Here are this morning's test results from my TF-100:
FC 4.5
CC 0.0
pH 7.2-7.5 (added 1/2 gallon of acid yesterday morning; it will be back up to 7.8-8.2 in a few days)
TA 90 (I'm trying to get it lower; it's hard with 200+ TA fill water and no rain)
CA 480 (two pool stores put it more like 300)
Salt 3600
CYA 60 (I know it needs to be closer to 80)
Borates 80
Any ideas as to what this could be?[attachment=0:3bulrxfw]Pool Pic 1.pdf[/attachment:3bulrxfw]
FC 4.5
CC 0.0
pH 7.2-7.5 (added 1/2 gallon of acid yesterday morning; it will be back up to 7.8-8.2 in a few days)
TA 90 (I'm trying to get it lower; it's hard with 200+ TA fill water and no rain)
CA 480 (two pool stores put it more like 300)
Salt 3600
CYA 60 (I know it needs to be closer to 80)
Borates 80
Any ideas as to what this could be?[attachment=0:3bulrxfw]Pool Pic 1.pdf[/attachment:3bulrxfw]