High TA...is it a big deal?

focalboy

LifeTime Supporter
Jun 27, 2007
24
Illinois
#1
I have had my pool up for 3 weeks now and I am close to having my SWG dialed in. I have used my Taylor DPD kit a few times a week to track my chemistry and here is my issue: my TA is 300, it was 310 until I used about 12oz of Muratic acid. My PH dropped from 7.6 to 7.4, my TA dropped from 310 to 290. Now it seems to be creeping back up. I have used JasonLion's awesome Pool Calculator and it shows my pool is balanced. Is my high TA something I need to address or can I accept it and enjoy my pool?

Here is my current levels:
FC= 3.2
CC= 0
PH= 7.4
TA= 300
Temp= 88
CYA= 65
CH= 210
salt= 3100
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#2
I expect that the PH will tend to drift up fairly quickly. At the same time you should keep your PH below 7.8 to prevent problems with scaling. That combination might be annoying and will require vigilance. If your PH behaves as I would expect, it would be much simpler to lower the TA right now to slow the rate of PH increase and push back the risk of scaling.

Working on lowering your TA doesn't need to interfere with your enjoyment of your pool. If you bring the PH down to 7.0-7.2 in the evening after you are done swimming for the day it will probably be up to reasonable levels by the next day with some aeration overnight and you can repeat as needed while swimming during the day.
 
G
#3
The high TA will make maintaining your pH difficult. It will always be rising fast. You will get better pH stability if you lower the TA down to about 70-90 ppm and increase the CH to about 300 to maintain water balance.
 

focalboy

LifeTime Supporter
Jun 27, 2007
24
Illinois
#4
So I add 13oz of MA in the evening to drop my PH to approx. 7.0. What is the best way to aerate? can I do it with my solar cover on? BTW I have not seen a rise in PH yet, and I was running my SWG pretty high early on.
 

JohnT

Admin
Mod Squad
TFP Expert
Apr 4, 2007
9,459
SW Indiana
#5
focalboy said:
So I add 13oz of MA in the evening to drop my PH to approx. 7.0. What is the best way to aerate? can I do it with my solar cover on? BTW I have not seen a rise in PH yet, and I was running my SWG pretty high early on.
No, you don't want your cover on. The low pH causes some of the carbonate in the water to change to dissolved carbon dioxide. Aeration allows the CO2 to be given off to the air. You want the water to churn as much as possible. A fountain is good. A bunch of people in the pool splashing around is good. Even pointing the returns so they ripple the surface will do it.

High alkalinity means it will take more HCL than you expect to lower pH, so add some, wait several hours, then retest and add more if needed.
 

focalboy

LifeTime Supporter
Jun 27, 2007
24
Illinois
#6
OK...So I get home this evening and do a complete test of my levels with my Taylor kit to have a base line before I add some MA. I have another problem. My FC had been slowly coming down from almost 5 about 10 days ago to 3.2 on Sunday morning. Today it is 0. Water temps have risen to 90 today, could that have anything to do with my lost FC?

I have added about 20 oz of MA and adjusted my return jet to break the waters surface as well as bumped up my Autopilot level. I'll check again tomorrow.

Thanks everyone.
 

Gimpy

LifeTime Supporter
May 27, 2007
40
Spring Hill, Florida
#7
Have you added any chlorine in the past 10 days? Have you tested for combined chlorine - what was the result? How does your water look?

If you have been adding chlorine, and can't keep up with its consumption, you've got something like algae using it up. I've never noticed a temperature rise having an impact on chlorine measurement. I use a SWG, and my FC measurement is steady at 2.0 ppm even with rising water temperatures.
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#8
When FC gets below 2 or 3 you should adjust the percentage and also suppliment the FC level with bleach. Any time FC gets too low you risk algae getting started and the SWG won't always be able to keep up with algae once it has gotten a foothold.
 

focalboy

LifeTime Supporter
Jun 27, 2007
24
Illinois
#9
I have not added any bleach since I started the pool. The water is crystal clear. The SWG has been giving me FC of 3.2 to 4.4 for the most part. twice I had CC of .2. I dialed my Autopilot back last week to bring it inline with my target of 3 and apparently that was too much. I'll get some bleach on the way home from work and test my FC again.

Maybe I missed it in the Taylor instructions, but can you test for CC if you sample does not turn pink in the FC test?
 
G
#10
It is possible to have no Fc but only Cc. The sample does not turn pink add 5 drops of the Cc reagent. If it turns pin then titrate to get your CC. This would mean that all the chlorine in your pool is CC and there is no FC.

Also, if your chlorine levels are very high you might need to add additional scoops of dpd powder to get the initial pink color. double check with the OTO test. If it turns color then you have chlorine in the pool.
 

focalboy

LifeTime Supporter
Jun 27, 2007
24
Illinois
#11
I used my test strips as well as the Taylor kit to check my FC levels before I added any Chlorine. I still have no FC after running the SWG for approx 10 hours. My CC is .2. What was the most shocking (no pun intended) was the PH rise from aeration. My PH is at least 8. The test strip shows 8.4, my Taylor is 8. I added more acid as well as adding 24 oz. of 12% Chlorine shock.
 

Gimpy

LifeTime Supporter
May 27, 2007
40
Spring Hill, Florida
#12
Jason, I've been running 80 ppm CYA, 2.0 ppm chlorine, and 50 ppm borates for nearly a year with no problems. I did have combined chlorine of 0.5 ppm one time after the first heavy rain of the season, but it went back to 0.0 ppm after a couple of days.

Before I added the borates I ran it at 4.0 to 4.5 ppm chlorine, and 80 ppm CYA and it would need to be shocked about every other month.

Your mileage may vary.
 

focalboy

LifeTime Supporter
Jun 27, 2007
24
Illinois
#14
Well I got my PH down to 7.8 and my FC up to 2.6 last night. I bumped up my Autopilot some more also. No more aeration for me until I get the Chlorine levels back to normal.

What are Borates going to do for me? Is this something I need to look at?
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#15
Borates have a number of advantages, easier to hold FC levels, clear sparkling water, less PH drift. But they can be a pain to add, the quantaties involved are large and you need to add acid to balance out the PH as you add borates. There is also a small risk to pets if they reguarly drink large amounts of pool water (people don't have a problem). I think of borates as more of a "hobbyist" project than something everyone should do.

If you are interested in borates get some borate test strips and aim for 30-50 ppm. You can calulate amounts of borax and acid using my Pool Calculator, see the link in my signature.
 

focalboy

LifeTime Supporter
Jun 27, 2007
24
Illinois
#16
Thanks Jason. I have a lttle dog that swims in our pool as well as licking water off of the deck. So maybe this is not for me.

Is it normal for 9-10 hours of aeration to raise my PH so dramatically?
 
G
#18
I have three small dogs and a cat and have had borates in my pool for about 2 years now and non of them have suffered any ill effects.
 

focalboy

LifeTime Supporter
Jun 27, 2007
24
Illinois
#19
Here are my results today. Looks like my PH bounced back pretty fast without any aeration. I added about 16 oz of MA and some CYA after my tests. My CYA dropped a little...maybe splash out?

FC 1.8
PH 7.8
TA 250
CH 210
CYA 55

Maybe Borates are in my future, Waterbear.