New (installed in July) fiberglass pool (SWG) has developed a bit of roughness on the vertical surfaces from water line to bottom...but more pronounced on the shaded side of pool. Will not brush or rub smooth.
Drained water down about a foot and effected area did not turn white when dry. It's actually not visible at all, just doesn't have the glossy feel of the area above waterline.
If this is scaling, I'm puzzled as my water has very low CH and I have diligently tried to keep my pH around 7.4-5...when it hits 7.6, I add pH down. Took a sample of water to my local pool store to compare to my readings and they were fairly close:
FC 6.56 (couple of ppm's higher than I normally run it, but with less sun and usage it had crept up)
pH 7.3 (I had just add pH down few hours before)
While realizing the CH level is way below your recommended min., I've been reluctant to increase it as a consultant at Leisure Pools (mfr of the pool) said I should never have to add Calcium to a fiberglass pool. Not sure I agree as I would think there are probably other things beside the pool shell that could be damaged by Calcium deprived water? Anyway low CH shouldn't produce scaling would it?
They sold me some PoolLife "Pool Plus". Put recommended 16 oz. in Tuesday afternoon, but so far no detectable improvement.
Pool is very small Roman style roughly 12 by 16 with a 3 ft. spa-like swim-out at one end.
Thank in advance for any insight you can add.