Calcium???

[AnnaK]

My test strips (AquaChem) test total hardness with a value at 0 presently. I just came back from Leslie's. Their test says 80 ppm calcium hardness and he wants me to add 18 (!) pounds of Hardness Plus. I said, I thought hardness didn't matter so much in a vinyl-lined AG pool and he said, oh yes it does because the water "wants to be hard and will leech what it can out of your liner, and stretch it".

But then, reading here on the Forum, I'm left with the impression that I really don't have to worry about hardness as long as the rest of my values are balanced, which they are.

If it were your pool, would you add Ca?

[CarlD]

There is one compelling reason for carefully maintaining calcium levels in a vinyl pool with either an SWG or a heater:

This is, of course, if the manufacturer's warranty of the heater or SWG requires that a certain calcium level be maintained.

[AnnaK]

This sure is a good place to come for information.

My issue with hardness is settled. I have neither a SWG nor a heater and I'm not adding 18 pounds of something I don't need to otherwise nicely balanced and clear water.

[CarlD]

This sure is a good place to come for information.

My issue with hardness is settled. I have neither a SWG nor a heater and I'm not adding 18 pounds of something I don't need to otherwise nicely balanced and clear water.

Why not? Just because the ONLY reason to do it is to transfer funds from your account to the pool store's?

Aren't you being a bit unreasonable?

[AnnaK]

It's all your fault, Carl. You taught me well.

[BrandonM7]

I know this is a three year old post, but it seemed like a good one to pick back up in regards to this --

What about the steps? What are the steps made of in a vinyl IG pool? I ask this because of the consideration given to fiberglass pools and potential gelcoat leaching. I have some bubbling and cracking of the face of 6 year old steps in my vinyl IG SW pool. I've kept the water well within acceptable levels the entire 6 years - not a single slip, honestly. And I keep it open and balanced year round. I know the levels I maintain have never gone out of whack (pH, TA, FC, cya) I have never maintained CH due to info from poolsolutions back when I started. Now my steps are bubbling and they won't cover warranty because my CH is 46ppm. I don't know that it caused the problem, but it's an easy out for them because I haven't kept it up. My bad there - should have kept it up for warranty alone. I'm wondering if I should go ahead and bump it up just in case that caused it - I figure having 100ppm isn't going to hurt anything anyway, and if it protects the steps from further damage that would be cool. I'd just like to know if it's responsible for the damage.

[waterbear]

I have never found any evidence that low calcium can damage the gelcoat in any way except for either higher incidence of staining or the formation of 'black spotting' or "cobalt spotting' which is actually cobalt crystallizing out of the gelcoat (gelcoat does contain colbalt). This look like little grey to black spot on the surface that start out pinhead size and grow into a 'crystal' that is raised from the surface. Newer gelcoat formulation are supposed to be more resistant to their formation.

I have seen firsthand that higher CH levels do help limit iron staining.