So...I just put in what Leslie's told me to (before I came here and bought my own test kit!!!).
My CH was 150. VINYL Pool....and they sold me a big tub of Calcium.
Live and learn.
What are the hazards of a CH of 500 in an SWG Vinyl Pool?
Water looks great. Didn't know if it was worth a partial drain and fill or if I should just let it deplete naturally.
TA 110 PH 7.5 FC 7 CYA 55 and rising (working on the FC and CYA already).