Total Alkalinity question

Jul 2, 2018
36
Jerseyville/IL
Pool Size
15000
Surface
Vinyl
Chlorine
Liquid Chlorine
My TA is 130….my pool math calculator says to lower TA, reduce ph to 7.0-7.2 with acid and then aerate to increase PH. My PH is 7.2.. my question is the acid; is it muriatic acid I use? If so how much would you suggest I put in?
My readings are

4 FC
1 CC
5 TC
200 calcium
130 TA
12 CYA (in the process of adding it)
10 BR
7.2 PH

*I have to add the borax and washing soda still this am
 
TA is an interesting one... there really is no need to do anything with it.. as you drop your PH the TA will also drop.. so just keep dropping PH and it will go down over time... when your PH gets to 7.8 drop it back to 7.2..

Lets talk about your FC and CC... With a CC of 1 you are killing stuff in your pool and that is a good thing.. is your pool cloudy or any kind of green?

Did you put in the whole amount of CYA to bring it to 30? if so just use CYA of 30... FC/CYA Levels so your target FC is between 4 and 6, try taking your FC to 6 every day and see if your CC goes down to 0, that is where you want it all the time...

no need to add borax or washing soda.. Those will raise your PH and your TA and you really want to bring those down..

Yes, you want to use Muriatic acid to take your PH and TA down :)
 
I suggest you aerate now to bring up your pH. Then use Pool Math app to determine the amount of muriatic acid to add to lower your pH back down to 7.2 This will also lower your TA. You need to know what your percentage of MA that you are using. 14.5% or 31.45%

The process of lowering pH and letting it rise again via aeration is a long process to lower overall TA. So be patient and over several days or weeks your TA will come down. Every pool is different.

Agree that you should bring up your CYA. FYI, CYA is measured in decade numbers (10, 20, 30, 40. Always use the higher number if the dot disappears between 2 decade numbers.
 
I would not add any Borax or washing soda. With your PH at 7.2 and alkalinity at 130, PH will rise on it's own and then you can drop PH when it gets to 7.8, which will drop alkalinity as well.
 
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TA is an interesting one... there really is no need to do anything with it.. as you drop your PH the TA will also drop.. so just keep dropping PH and it will go down over time... when your PH gets to 7.8 drop it back to 7.2..

Lets talk about your FC and CC... With a CC of 1 you are killing stuff in your pool and that is a good thing.. is your pool cloudy or any kind of green?

Did you put in the whole amount of CYA to bring it to 30? if so just use CYA of 30... FC/CYA Levels so your target FC is between 4 and 6, try taking your FC to 6 every day and see if your CC goes down to 0, that is where you want it all the time...

no need to add borax or washing soda.. Those will raise your PH and your TA and you really want to bring those down..

Yes, you want to use Muriatic acid to take your PH and TA down :)
Pool is a tad cloudy. I’m adding stabilizer right now. It called for 5 pounds last night. I added 2 1/2 last night and retested this am. Added 2 this am. We have had SO much rain for so many days it threw off everything. That and my husband complains if the pump runs too long 🙄🙄.
Thanks! I’ll add the acid tonight 🙂🙂
 
If the water is cloudy you may want to do an Overnight Chlorine Loss Test tonight.. run the pump 30 minutes just as the sun goes down and test the water... Wake up before the sun comes out and turn the pump on for 30 minutes and test the water again...

If you lose more than 1 FC you should do a SLAM Process :)
 
What CYA are you shooting for? Dose FC based on the CYA already being in the water. Use the FC/CYA Levels.

Do not add borax or washing soda. Just aerate the water. Your TA is high enough that the pH will rise on its own.
No real need to worry about TA. It will drop on its own a little each time you add acid. The only real need to force TA down is if you have high TA fill water. Test your fill water and report findings here.

Fill water (just the two items listed)
TA
CH

When reporting pool test results, use the following format. No need to report TC (FC + CC = TC).
FC 4
CC 1
pH 7.2
TA 140
CH 200
CYA 12

How did you test a CYA of 12?
No need to report BR as you don't have a bromine pool.
 
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