Need some fresh advice on CH

[lindz18]

My calcium hardness is currently at 40. I know the recommended level on the chart is way higher, but when I search this in the forums I get the opinions that it isn't important to my pool. I just want to make sure. I don't want to be so accurate in everything else and let this slip by me and cause myself future problems even though I think the previous owner done enough damage for all of us if it needs to be controlled. My father in law states that it is a necessity that I maintain it to proper levels. He is on a SW system. He is, however, one of those pool store followers on the dark side

Here's my test from this morning on everything else:

FC- 11
CC- 0
TA- 70
pH- 7.8
CH- 40
CYA- 90 (I'm getting there!!! )

 

[Azgirl71]

With a vinyl pool there is not as much concern about the CH level.

 

[tim5055]

Let him follow the pool store. You do not need CH with vinyl. Our recommendation for your pool would be "CH 0-350 (Don't add)"

Did you see something different at TFP that was "higher"?

 

[JVTrain]

Your numbers look great. The CH is "low", but there is NO reason to raise it with a vinyl pool surface. Low CH is not hard on pumping equipment or ladders, etc. either so nothing to be concerned about there.

 

[lindz18]

Somewhere I saw 220-350 but I may have misread a post. They may have been stating what the dark side told them the proper level was. I just wanted to get some fresh perspective! Thanks, guys!!! I feel like I am finally getting this pool in order and being MY pool instead of me being the POOL's caregiver and master.

- - - Updated - - -

With a vinyl pool there is not as much concern about the CH level.

Thanks, friend! You are always a help! Do you need any rain out there ? Got plenty here! Ugh.

 

[tim5055]

Somewhere I saw 220-350 but I may have misread a post. They may have been stating what the dark side told them the proper level was. I just wanted to get some fresh perspective! Thanks, guys!!! I feel like I am finally getting this pool in order and being MY pool instead of me being the POOL's caregiver and master.

There are different recommendations for pool surface and chlorination method.

 

[JoyfulNoise]

The practical experience of thousands of vinyl pool owners shows that there's no demonstrable advantage or disadvantage to maintaining a particular CH level. Pool stores and and the pool industry try to make hand-waiving arguments about needing to maintain a specific CH range because calcium carbonate is used as a filler in PVC and vinyl but there is little definitive evidence that suggests that a particular CH range is advantageous for vinyl. For plaster pools, one can use the chemistry of plaster materials in pool water to make a more specific recommendation for an exact range. For vinyl, liner manufacturers use vinyl starting materials from various sources and suppliers all of whom have their own proprietary vinyl/filler formulations to satisfy their manufacturing processes. That variability alone makes it impossible to be very specific about CH levels with respect to the vinyl surface.

If you take the liner out of the question, and only focus on water quality and scaling issues, then a range of CH values can be proposed that would satisfy both of those parameters. I believe the current TFP CH levels for vinyl are suggested so as to produce a pleasant feeling water quality (hardness of water on skin and clothes) as well as to keep the water's CSI (calcite saturation index) in an appropriate range relative to the other suggested values (pH, TA, CYA, etc) to avoid calcium carbonate scaling.

The short answer - you're totally fine and I'm totally jealous! I live in a place where the fill water CH value is 280ppm (minimum) and I'm watching my CH creep up season after season....

[EDIT]
See this thread for an interesting and in-depth discussion.
[END-EDIT]