Why is the recommended Calcium Hardness so high?

[MediaManGA]

Hi all. Trying to adopt the TFP method for my new pool this time around (instead of just whatever Leslie’s says). Plaster pool with PebbleTec , SWG.

I’m scratching my head at the Pool Math app’s recommended Calcium Hardness. My builder suggested 200-300. Most posts in the forums are 200-350. Leslie’s recommendation is 200-400. But the ideal range in the app is 350 - 550. Why is it so high? Doesn’t too much calcium cause buildups and damage equipment?

What am I missing?

Thanks!

 

[mknauss]

Welcome to the forum!
If you have the pH, TA, and CH in the ideal ranges, then the CSI is near 0. But it is nearly impossible for most of us to achieve that and truly not necessary as a practical matter. Many fill waters are high in TA, or CH. And thus some of us have to manage differently.
If your CH is in the lower recommended range, then a higher pH will compensate.
Do not focus on 'ideal'. Focus on acceptable.
I suggest you read through Pool Care Basics - Trouble Free Pool and even look at a few of our videos TFP-TV - Trouble Free Pool