Was at Leslie's seeing if they could loosen the pump impeller for a rebuild. I was telling them about the chemicals that had come with the pool I acquired and they said that Cal-Hypo was bad for vinyl liners. They said they wouldn't warranty a liner that had Cal-Hypo used in it. I'm new to this pool stuff but have done some reading here and elsewhere and hadn't heard this. I hadn't planned on using the Cal-Hypo as I have high calcium levels in my fill water. This is only the second time I've been in a pool store and after reading about them here I take everything they say with lots of skepticism. :-D I'd just like to know the truth so I ask here.