Water Balance Questions

JLA956

Bronze Supporter
Oct 24, 2017
10
Dallas, TX
Our new spa (400 gallons & planned temp setting of 103) will be arriving this next week and I plan to implement the Bromine method outlined by Molson in the thread - How do I use Bromine in my spa? That posting refers to another thread about first balancing your water before implementing the bromine procedures. In the referenced thread by Nitro (How do I use Chlorine in my spa?) he notes several steps to balance out your pH, TA, and CH which are very straightforward. Toward the end of that posting he does mention the recommendation of adding Borates with a product called Gentle Spa. My specific question is when exactly to add the Gentle Spa product during the balancing process?

Per Nitro's suggestion and using a Taylor K-2106 test kit I was able to determine the following from our tap water that will be used to fill our spa:

  • CH = 130
  • TA = 100
  • pH = 8.0 (one drop of R0005 dropped the pH to 7.6 and two drops brought it down to 7.2)

So, in following his balance procedures I know that I will be adding some acid to bring down the TA and the pH while following his detailed instructions regarding running the jets while working on the proper balance. Any recommendations as to a dry acid vs. muriatic acid? What would last the longest shelf-life wise?

My question about this Borates is should I add them after everything is balanced or prior to introducing the acid to adjust the TA and pH? I plan to use the Gentle Spa product that he recommends at around 50 ppm.

Next question, what is the shelf life of Bromine tablets? Our friend has a large tub of bromine tablets that he will give us but he said that there are around 3 or 4 years old. Would they still work in our bromine floater or would it be best to get new ones?

And lastly, we picked up a gallon of bleach today while we were in WalMart - it's called Great Value Concentrated and it states on the label that it's 8.25% sodium hypochlorite (yield 7.86% available chlorine). All of the formulas in the Bromine Spa Treatment method are using bleach strengths of 5.25%, 6%, or pool chlorine of 12.5%. How can I best adjust these formulas for taking into account this bleach that we purchased?

Thanks in advance to everyone for their feedback and recommendations - this is a great community and resource!
 

pooldv

TFP Expert
Platinum Supporter
LifeTime Supporter
Moderator Emeritus
Aug 10, 2012
25,412
FL panhandle
Welcome to TFP!

Muriatic acid is better. Dry acid contains sulfates which will build up over time nd attack metal and concrete surfaces.

Add borates after TA is lowered.

I don't know much about bromine pucks but I would expect if the pucks stayed dry that they will be fine to use.

Use PoolMath, link at top of each page. 8.25% is one of the options and you can use the Effects of Adding Chems section toward the bottom to predict outcomes.
 

JLA956

Bronze Supporter
Oct 24, 2017
10
Dallas, TX
Thanks for pointing out the section of PoolMath that deals with bleach concentrates - I just didn't scroll down far enough to see it. I assume that the output results in the "Effects of Adding Chemicals" section is based upon the gallon size that is entered at the very top? Also, thanks for your suggestion regarding Muriatic Acid and the Borates.

Welcome to TFP!

Muriatic acid is better. Dry acid contains sulfates which will build up over time nd attack metal and concrete surfaces.

Add borates after TA is lowered.

I don't know much about bromine pucks but I would expect if the pucks stayed dry that they will be fine to use.

Use PoolMath, link at top of each page. 8.25% is one of the options and you can use the Effects of Adding Chems section toward the bottom to predict outcomes.