What is the right goal for Calcium Hardness in a hot tub?

[amandabee]

Based on some solid advice on Reddit, I've been using the Pool Math app and reading through this TFP thread How do I use chlorine in my spa?

My random test strips recommend Total Hardness (calcium and magnesium) between 250 and 500 ppm. The thread here says to aim for a Calcium Hardness of 130-150ppm. The app says my recommended range is 250-650 (I assume PPM?) and the ideal would be 350-550. My actual reading is coming in just under 100ppm.

I'm not sure how to decide which value is accurate. Total Hardness vs Calcium Hardness is also a bit of a puzzle.

 

[ajw22]

Calcium Hardness - Further Reading

www.troublefreepool.com

If you have a spa you might want to keep CH at at least 100ppm to 150ppm to reduce foaming.

If you don't have foaming I would not worry about your CH level.

I think PoolMath is giving you pool recommended levels and not standalone spa levels.

 

[Mdragger88]

If your spa is acrylic or roto molded put in vinyl for the settings.
Ditch the strips - the ranges are simply too broad even if they were accurate.
Get a taylor k2006 or tf100
Test Kits Compared

 

[Methuselah]

Sounds like you're off to a great start, welcome to TFP!

 

[amandabee]

If you have a spa you might want to keep CH at at least 100ppm to 150ppm to reduce foaming.

If you don't have foaming I would not worry about your CH level.

Oh, I have foaming!
I also have a teenager with friends and I just assumed that the foaming was because they're all teenagers who use too much laundry detergent and axe body spray.

 

[Mdragger88]

Oh, I have foaming!
I also have a teenager with friends and I just assumed that the foaming was because they're all teenagers who use too much laundry detergent and axe body spray.

That’s also a huge possibility- & the hair conditioner with girls! I have a strict no hair in the hot tub policy- you wanna swim, get in the pool!