Nitro or Chem Geek - TA level?

[Terv]

Hello,

My recent 320 gal hot tub refill of city water was: 46F, pH 8.0, TA 50 & CH 50 out of the tap.

After balancing, the hot tub water is: 100F, 4ppm Br, pH 7.8, Borate 60-80, TA 50 & CH 150.

The water looks and feels clean. I have no issues with foam or any kind of build up.

Nitro recommends TA 80 and Chem Geek recommends TA 50 with Borate 50.

I find it difficult to raise the TA to 80 and then get the pH back down to 7.6-7.8. (I use baking soda and pH Down)

QUESTION: Have I misread the stickies? Which TA number should I be adjusting to? 50 or 80 ppm?

Thank you,

 

[jza1736]

I had the same issue. The spa calls for 80 TA, but I couldn't get the PH below 8. I road the roller coaster for about a week.

The spa likes 50 TA and the PH is happy at 7.5.

 

[pooldv]

50 is the TA number for a spa. I don't see any reference to 80 in the Nitro post here, How do I use Chlorine in my Spa (or pool)?

 

[jza1736]

My TA 80 was from the manual

50 is the TA number for a spa. I don't see any reference to 80 in the Nitro post here, How do I use Chlorine in my Spa (or pool)?

 

[Terv]

Hello,

My error I got Chem Geek and Nitro reversed.

See the screen print below with the TA recommendation in red. Note it is with a condition ..... using Bromine tabs. (which I use)

chem geek

Join DateMar 2007LocationSan Rafael, CA USAPosts12,082

[h=2]Re: Low TA perfect PH in Spa[/h]

Welcome to TFP!

Are you using bromine tabs in a floating feeder? If so, bromine tabs are acidic and given your lower pH you'll want the TA to be higher to compensate. You could raise the TA to 60 to see how that goes and if the pH still tends to drop over time then raise the TA to 80, etc. Basically, you want to find a TA level where your pH tends to be stable over time. Note that the TA will slowly drop over time due to the acidic bromine tabs.

You can use The Pool Calculator to calculate dosages. Add the baking soda very slowly to the water with the circulation pump on, but not the jets. That will minimize how much the pH rises. It's OK for the pH to be in the 7.7 to 7.8 range, especially with bromine, though if it settles in at 7.5 then that's fine as well.​

I will continue to follow Nitro's Summary Recommendation at the bottom of the sticky.

Thank you.

 

[ant 83]

This question keeps coming up. Over and over again.

The non-TFP answer is that if you are not calculating CSI (do not have plaster or grout), you should ignore TA completely, and just adjust PH.

If PH is too high, lower it, if it's too low raise it. By small increments, tested daily.

This is the answer.

 

[ScubaJules]

This question keeps coming up. Over and over again.

The non-TFP answer is that if you are not calculating CSI (do not have plaster or grout), you should ignore TA completely, and just adjust PH.

If PH is too high, lower it, if it's too low raise it. By small increments, tested daily.

This is the answer.

I understand what you are saying. However, as someone who fought pH drift for over a month (with TA=80, CH=180, CYA=30, T=90 F, and so on) - after I began lowering the TA in my fiberglass spa, voila! My pH settled down. I trust the water gurus/chemists around here and the sticky posts are invaluable.

The spa manuals and spa dealers say to keep TA between 80-120. No, the spas don't have grout or plaster, but when manuals and dealers say "do this"... well, we do. It is only through reading a million posts that I was convinced to lower my TA below 80 and find the number that helps the pH stay reasonable in my spa - given the million factors (use, aeration, sun, chemicals, yada yada) that change pH. It sure wasn't working when the TA was between 80-120.

So, yeah, getting the TA sorted out can really help.

Anyhoo, that's my two-cents as to why the question keeps coming up. Blame dealers, manufacturers and instruction manuals.

If only the instructions given to noobs upon the purchase of a spa went:

50 is the TA number for a spa. I don't see any reference to 80 in the Nitro post here, How do I use Chlorine in my Spa (or pool)?

That's the ticket!!

 

[Spa Owner]

The spa manuals and spa dealers say to keep TA between 80-120. No, the spas don't have grout or plaster, but when manuals and dealers say "do this"... well, we do. It is only through reading a million posts that I was convinced to lower my TA below 80 and find the number that helps the pH stay reasonable in my spa - given the million factors (use, aeration, sun, chemicals, yada yada) that change pH. It sure wasn't working when the TA was between 80-120.

The dealers are repeating whats in the manual.

The manual is repeating industry 'lore' as fact.

 

[ant 83]

The spa manuals and spa dealers say to keep TA between 80-120.

The reason for this is because they want you to buy paper dip strip testers that cost more money. They don't work. So, test for TA instead of PH.

Also they want to sell you dichlor instead of bleach. Bleach is very close to PH neutral, whereas dichlor is acidic. Having a higher TA means longer before the water turns corrosive. They want you to come to the store to test your water to sell you stuff. That doesn't happen often enough to keep PH correctly balanced.