Relationship of CH level to TA/pH levels in spa

[FLPoolDIY]

After reading the sticky post “how do I use chlorine in my spa or hot tub” there is a statement “The CH level will be used to determine your TA/pH levels.” For the life of me searching through the site I can’t seem to find the answer to this.

How is the CH level used to determine my TA and pH level.

I’ve had my spa for about 3 weeks and feel like I have things pretty balanced out using Dichlor/bleach method. I had a pool At my previous house so pretty familiar with the TFP methods and water testing with the exception I had a SWG for the pool so dealing with the daily addition of chlorine is a bit of a PIA. The spa did come with an ozone unit which after reading multiple post is probably contributing to the daily dosage of chlorine.

My pH has been pretty stable and the only issue I really have is quite a bit of foam when all jets have air full open. IMO kind of expected and it disappears quickly after jets are turned off.

Test results as of this morning using K-1005 DPT with FAD-DPT and SpeedStir.

FC 2.0
CC .5
pH 7.6
TA 60
CH 125
CYA 30

463 gallon Vita Luxe 300 spa.

 

[PoolStored]

That is a VERY old thread. Thinking has evolved. The issue the OP was talking about was scaling in a hot tub. If CH is high enough, you can lower TA and pH to reduce likelihood of scaling.

Use this instead of the post you referred:

Spa & Hot Tub Maintenance A Basic Guide

Hot Tub Maintenance can be done easy with a few tricks. Hot tub chemicals, rashes, and schedules are all covered in this easy to grasp article.

www.troublefreepool.com

It is not very likely to get scale with your numbers, but use pool math, turn on TRACK CSI and Track TEPERATURE. CSI can give you a sense for scale potential.

CSI and LSI - Further Reading

www.troublefreepool.com