Low CH

[Lizzieann]

Pool store person said may need to add calcium increaser if level is too low. (haven't tested mine yet as trying to just clear it up right now). He said if there is not enough calcium in water that it will be pulled from "wherever" it can, like the liner and make it brittle.
I have read on here that calcium hardness does not matter in a vinyl liner. Why is that? and is he feeding me "pool store" Poo?

 

[Bama Rambler]

Yep, he's feeding you a line.

I've had zero (yeah, you read that right, ZERO) CH (Calcium Hardness) for as long as I've owned the pool and the liner is still as supple and flexible as it was new. And that's been about 5 years.

 

[Richard320]

What he meant was "I need to sell you something."

Don't fall for high TDS/Nitrates/Phosphates either. I've never had mine tested and my pool is crystal clear.

 

[Stuamurr]

Low CH in a liner pool is not an issue as there is nothing to erode (no plaster/grout), the water is not corrosive enough to attack metal either so increasing your CH is just an expense you dont need. Only thing I would say it gives you is the flexibility to use Calcium Hypochlorite if you see it at a good price if your CH is low already.