It seems the recommended CH levels have a huge range. I have a tiled pool.
Test results (taylor 2006):
FC - 1.2-1.4 (low because I'm doing a bioactive test to try to lower CYA)
CC - 0-0.2
pH - 7.4
TA - 140
CH - 110
CYA - 110
I'm currently increasing CH with calcium chloride, but I'm not sure how high I should go. The recommended range of 150-400 is very broad. Does a tiled surface matter? Do any of the other numbers matter on where CH should be?