Tackle TA before adding chlorine?

[JodieM]

Just purged the hot tub with Ahhsome, drained and refilled with tap water.
Here are my tap water results:
FC 0
PH 7.5
TA 310
CH 175
CYA 0
Tub 250 gallons

Should I tackle the TA problem first or is it ok to get some chlorine and cya in there while working on TA?

 

[tim5055]

I'll be honest, I don't think I've ever checked the TA in any hot tub I've owned......

Start the CYA/Chlorine before the water gets cloudy

 

[JodieM]

Thanks Tim.

 

[jseyfert3]

I always add chlorine before I start the acid-aeration process to knock the TA down (my fill TA is in the same range as yours). If possible (not winter) I start the acid-aeration process immediately on filling before I heat cause all the aeration is energy intensive.

I'm assuming this is a standalone hot tub? (I don't see it in your signature)

 

[JodieM]

Yes. It’s stand alone. I put the chlorine in the night we filled it. Checked yesterday evening and the PH was over 8.2. I added 2.3 oz of dry acid. Will check the levels again today. Need to go get some stabilizer today. Then I test TA/FC/PH again.

 

[tim5055]

I'm on my 7th stand alone hot tub. Maybe I've been lucky, but I never had one that pH went up, it has always fallen for me. I regularly have to raise the pH, not lower it....

For stabilizer you can just chlorinate with Dichlor until you get to the correct CYA if you have that around.

Remember, this is a temporary body of water. Most people drain/refill 3 - 4 times a year. Because I'm on a well with high iron I have reduced that to every 6 months. If your source water is high TA and you are going ot have to fight it down every refill, you may be extending your refill schedule also.

 

[jseyfert3]

I'm on my 7th stand alone hot tub. Maybe I've been lucky, but I never had one that pH went up, it has always fallen for me. I regularly have to raise the pH, not lower it....

What's your fill TA?

With my TA levels (I get 350-400 ppm testing our tap water), I can start with a pH of 7.2, run the jets with air for 20-30 minutes, and it will peg the pH test on the high side. If I want to run air without drastic pH rise (and my wife enjoys using air in the jets), I need to spend a few hours on the fill doing acid/aeration cycles to knock the TA down. In my experience, once the TA drops below about 100 the pH rise becomes a lot more manageable.

If I'm not running air in the jets, then the TA isn't as much of a concern, as the pH rise is very slow.

 

[tim5055]

I have had these tubs in multiple locations from Florida to Washington DC over the past 40 years. I haven't een tested the TA of my well water, but with nothing to do, I may do it today just for giggles.

 

[JodieM]

If your source water is high TA and you are going ot have to fight it down every refill, you may be extending your refill schedule also.

Yes, our source water is very high in TA, 310 out of the tap. We drain and refill about every 4 months. Should I even worry about TA? or just keep adjusting PH regularly and let TA fall on its own?

For stabilizer you can just chlorinate with Dichlor until you get to the correct CYA if you have that around.

I don't have any dichlor on hand. So I may as well get stabilizer, I can always use it for the pool if needed.

 

[jseyfert3]

Should I even worry about TA? or just keep adjusting PH regularly and let TA fall on its own?

Do you run air in your jets? If so, I'd recommend the acid/aeration process to knock the TA down. If not, then you can just add acid when the pH says to.

 

[JodieM]

J,
I don’t know the answer to this. We have a simple stand alone hot tub with a Jets on low and jets on high function.

 

[jseyfert3]

When the jets run, do they pump out lots of air bubbles with the water or is it just water?

On our tub, we have air valves. So we can run jets with or without air. The air gives the jets more of a "vigorous" feeling. I would be surprised if even your simple tub did not have this option, as even our single person jetted bathtub has air valves for this purpose.

 

[dlleno]

Do you run air in your jets? If so, I'd recommend the acid/aeration process to knock the TA down. If not, then you can just add acid when the pH says to.

this! I find that chasing a TA number is just not fruitful. and in a portable acrylic spa you can afford to let the saturation index go negative; I find some surprisingly low TA numbers in my spa ( if you target the saturation index) , but they are a don't care. I'll test to make sure things don't go too low, as I don't want a precipitous pH drop, but so far the lowest I've seen is 50.