My calcium hardness in my 25k vinyl pool is 60 which is the same as what I receive from the local reservoir. Leslies says I should add 60 lbs of Calcium Hardness to bring the CH up to 320. From what I read by Googling around, you don't have to raise the CH for a Vinyl pool. If, by chance, the CH should be raised for a vinyl pool to some minimum level, what would be a good target?
