Borax/Acid or Boric acid

D&GNewbies

Well-known member
Jun 25, 2020
82
Iowa
So our levels seem good today. Well, better :)
FC 7.5
CYA 60
pH 7.6
TA 150

I still would like to get our TA down and then add borax or boric acid. IF, I calculated it, I would need to add 35 pounds of boric acid OR 30 pounds of Borax and and then an additional 3 gallons of muriatic acid to lower the TA and pH back to range

I am so confused.
 
And if I remember right, once I add either borax or boric acid, it stays in the water other than evap or splash out? It wouldn't be something we would need to add on a weekly etc basis. And it "should" make the water softer, sparkle and maintain pH better.
 
You would have to price out for convenience and cost, but you can buy granular (not powder) boric acid from Duda Diesel. This is what I use just because it is easier for me, plus finding that much borax at the store can be tough.
I can definitely order boric acid.
Our main reason for wanting to add it is because the water feels hard. Similar to hotel shower water, so your skin is dry when we get out. Our hardness is at 275. I thought borax and boric acid would help make the water feel softer as well as keeping the TA and pH from fluctuating. We do have to add about a 1/4 of water every few days right now because of splash out and overnight evap. It's been super hot and humid here during the day and then drops to mid to low 60's at night.
 
Evaporation won't change your borate level. The splash out will since the water left the pool. In the larger scheme of things how much do you splash out? I've used Borax and boric acid. The Borax because it was convenient and I was adjusting the water. Later when I had PH where I wanted it, I used boric acid to avoid using muriatic acid. I purchased the boric acid in bulk but it came in 5 or 10 pound bags. That let me add it slowly over several days so I didn't overshoot.
 
Evaporation won't change your borate level. The splash out will since the water left the pool. In the larger scheme of things how much do you splash out? I've used Borax and boric acid. The Borax because it was convenient and I was adjusting the water. Later when I had PH where I wanted it, I used boric acid to avoid using muriatic acid. I purchased the boric acid in bulk but it came in 5 or 10 pound bags. That let me add it slowly over several days so I didn't overshoot.
We have kiddos swimming everyday and they do tend to splash alot but not an insane amount, so we may be ok.

So borates are ok to add then? I am happy where the pH is at, just the TA is still high but everything else looks good.
 

Enjoying this content?

Support TFP with a donation.

Give Support
The water sparkles and my wife likes the feel. My PH/TA seem to be more stable since I added it. Search Borates / Borax and you can find several articles about adding them.
 
that's definitely my plan. i have to get more acid tonight after work. i am hoping just a couple more additions and we can be done.


If you plan on keeping the pool open and usable while lowering TA, it will take longer than a couple of more additions. Using acid to take pH from the top of the safe range to the bottom of the safe range is only going to lower TA by 8-9. I opened at 140 TA and it has taken all summer to get it down to 80.

If you add acid to drop pH to around 7.2-7.4, how long does it take to creep back up to 7.8-8.0?

Also, as you are able to lower the TA, the rate of pH change slows as well, so it takes longer to get from 100 to 80 than it does 140 to 120. A lot longer.
 
If you plan on keeping the pool open and usable while lowering TA, it will take longer than a couple of more additions. Using acid to take pH from the top of the safe range to the bottom of the safe range is only going to lower TA by 8-9. I opened at 140 TA and it has taken all summer to get it down to 80.

If you add acid to drop pH to around 7.2-7.4, how long does it take to creep back up to 7.8-8.0?

Also, as you are able to lower the TA, the rate of pH change slows as well, so it takes longer to get from 100 to 80 than it does 140 to 120. A lot longer.
We did our first water sample on 07/20 and our TA was over 273ppm. It's come down quite a bit, but seems the rate of change is slowing.

On 7/28 we tested at home and at the pool store we switched too (love them) our results were:
FC- 5.6
pH 7.8
TA 170
CYA 60
So we were told to add one gallon of muriatic acid. We did. So I tested yesterday 07/29 and pH went down to 7.2 and TA to 150.
This morning I tested and pH was 7.6 TA still at 150. We did have kiddos swimming last night, but not sure if that makes a difference.
I did add liquid chlorine because based off the CYA chart we want to keep our chlorine between 7-9 and our FC this morning was 7.5.
 
So I tested our tap water since we use our outside hose to fill our pool when it needs topped off. The TA is 325! So no wonder we are having a heck of a time lowering our TA. We've had to add water a couple times due to overnight evap and splash out. Not a lot, maybe 1/2 inch or so total.
 
A gallon seems like a lot of acid for 13,000 gallons. Did you use the lighter solution (@14%)

I use the 31% acid and add about 24 ounces to 16,000 gallons to take my pH from 7.8 to 7.4.

I just looked at my recent logs. It took 11 days to get from 100 to 90 and took 18 days to get from 90 to 80.
 
This is a great thread to read


It alks about the test that can be done with things you have, plus a few more to add. Keep at or below 50ppm.
 
A gallon seems like a lot of acid for 13,000 gallons. Did you use the lighter solution (@14%)

I use the 31% acid and add about 24 ounces to 16,000 gallons to take my pH from 7.8 to 7.4.

I just looked at my recent logs. It took 11 days to get from 100 to 90 and took 18 days to get from 90 to 80.
No, we used the 31%, which is why I am shocked it's taken this long to lower it. I want to add boric acid soon, but can't until we get our TA lower.
 
What are you hoping to accomplish with borates? Steadier pH? You'll get that if you ever get the TA down to about half where it is now. Every time you replenish the water you're just going to drive TA, and by extension, pH, upwards. And it will take more acid to lower pH once the borates are there. Borates might slow it down some, but again, so will aggressively driving down the TA now.

When you add water, don't just drop the hose in. Rig it with a spray nozzle on a ladder or on the fence somehow so it blasts the surface. That'll push the pH back up fast so you can re-treat it with acid. Devise a jet on the return so it breaks the surface. Acid, aerate, repeat until TA comes down. Then things should stay steadier to where you only need to add acid after water replacement.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.