Vinyl Pool and Calcium

[anotherpyr]

I run a vinyl pool without a heater and I've always been told that the CH didn't matter since I didn't have a heater. Of course if it gets too high and the saturation index goes over 0.3 you'll get scaling.

The Pool & Spa Water Chemistry guide which came with my Taylor test kit says that if the saturation index drops below -0.3 then it may cause corrosion of concrete and possibly metal surfaces.

So its more a question of how risk adverse you are. If possibly keeps you up at night, then add it and get a good nights sleep. It hasn't kept me up yet. But I do wonder about it occasionally.

Turns out there is an interesting conversation on this subject in this post http://www.poolforum.com/pf2/showthread.php?t=6891.