Stuck in a TA-pH loop, need some advice

[capybaras]

This is my first year opening my pool, in general opening went well but I'm having trouble with TA and pH. Also please forgive any noob mistakes, here to learn!

When I opened the pool, it was mostly clear but the TA was way higher than I expected it to be.

I tried raising the pH by aerating, but I clearly don't know how to do that properly and seemed to only raise due to rain?

I ended up following a regiment of lowering TA and pH with muriatic acid, then raising pH with Borax, then repeating.

Date	CYA	TA	pH	FC	TC	TH	Notes
Opening	20	690	9	0	0	225	Clear, added 1 gallon acid
	20	280	7.2	0	0	225
	20	360	6.8	0	0	225	Rained, aerated
	20	440	8.2	0	0	225	1 gallon of acid
	20	280	6.8	0	0	225	4 boxes borax
	20	450	9	0	0	225	Murky water 2 qt acid, rained, added 1 x trichlor to skimmer
	20	340	6.8	0	0	225	Still murky. 1 gallon liquid chlorine. Temp high enough for salt cell, installed. 2 boxes borax
	20	420	9	0.5	1	225	1 gallon acid
Today	30	380	7.6	0.5	1	225	2 boxes borax

I feel like I am stuck in this loop of trying to lower TA + pH with acid, then raising pH, then starting all over again. It's been about 10 days and I feel like I've made no progress.

 

[RonsPlc]

If you have water features... waterfall, sprinkler, etc, they will raise your PH without bringing the TA up with it.

I made a sprinkler out of PVC that I jammed into my return after removing the eyeball that did the trick for me when I was lowering my TA a couple of years ago.

 

[mknauss]

I have never seen TA values that high. What is the TA of your fill water? Did you add copious amounts of baking soda?

 

[Stump]

I`ll steal mknauss`s thunder question what test equipment methods are you using?

 

[capybaras]

If you have water features... waterfall, sprinkler, etc, they will raise your PH without bringing the TA up with it.

I made a sprinkler out of PVC that I jammed into my return after removing the eyeball that did the trick for me when I was lowering my TA a couple of years ago.

I saw a video of this on youtube, I have to give this a try

I have never seen TA values that high. What is the TA of your fill water? Did you add copious amounts of baking soda?

The company that built the pool (awful experience) closed the pool without telling me (I was at work), so I'm not sure exactly what they did (grr).

Over the course of the first season, the TA was averaging 80-100 (slightly high). I recall adding baking soda once, maybe mid season (not in my notes though).

The fill water TA is 90 (pH is 7.2)

I`ll steal mknauss`s thunder question what test equipment methods are you using?

TF-100

 

[mknauss]

It would take 1500 oz of baking soda to go from TA of 100 to 380 in your pool. Nearly 100#. I doubt any pool service would have added that.

Check your testing methods. Read Pool School - Total Alkalinity

- - - Updated - - -

Reading more closely, why are you adding borax? With TA of 100 or above your pH will rise all by itself with little aeration help.

 

[capybaras]

It would take 1500 oz of baking soda to go from TA of 100 to 380 in your pool. Nearly 100#. I doubt any pool service would have added that.

Check your testing methods. Read Pool School - Total Alkalinity

Not sure what to say, I believe I am doing it exactly as per the instructions (same as that link)

Reading more closely, why are you adding borax? With TA of 100 or above your pH will rise all by itself with little aeration help.

Well, first of all I'm new .

I decided to add Borax because I saw my pH was at the correct level, but I still needed to add acid to lower the TA. In order to do so, I knew I had to raise the pH.

I first tried aerating (honestly I do not really know what I am doing for aeration) by pointing all my returns up (more of a ripple effect really), and when adding fill water I put the hose up high and with an aeration tip. Fwiw, I used the pool calculator to tell me how much borax to add.

Perhaps I wasn't patient enough, but I didn't really see a pH increase at all. Suggestions?

 

[mknauss]

Follow Pool School - Lower Total Alkalinity

To get aeration point the returns up and crank the VS pump as high as it will go. If you can getting in and splashing like crazy helps too. I find it takes several hours of aeration to get the pH from 7.2 to 7.8 with a TA of 100. I would think with a TA north of 300 it would not take long at all.

There are alot of aeration devices described in the forum. Do a search.

Good luck.

 

[capybaras]

Follow Pool School - Lower Total Alkalinity

To get aeration point the returns up and crank the VS pump as high as it will go. If you can getting in and splashing like crazy helps too. I find it takes several hours of aeration to get the pH from 7.2 to 7.8 with a TA of 100. I would think with a TA north of 300 it would not take long at all.

There are alot of aeration devices described in the forum. Do a search.

Good luck.

Thanks for your help, I'll give aeration another (better) try

 

[ajw22]

.

I decided to add Borax because I saw my pH was at the correct level, but I still needed to add acid to lower the TA. In order to do so, I knew I had to raise the pH.

I first tried aerating (honestly I do not really know what I am doing for aeration) by pointing all my returns up (more of a ripple effect really), and when adding fill water I put the hose up high and with an aeration tip. Fwiw, I used the pool calculator to tell me how much borax to add.

Perhaps I wasn't patient enough, but I didn't really see a pH increase at all. Suggestions?

Be more patient. It will take time for the PH to drift up and the TA to decrease.

I am in the process of lowering my TA from 110 to between 60 - 70. It has taken over 5 cycles of knocking my PH down to 7.0 and letting it drift up to 7.8. My ph rises about .4/day.

If you look at the bottom of PoolMath you will find Effects of adding chemicals. If I put in 128 ozs of MA in my 35,000 gal pool it says it will lower PH by .88 and lower TA by 14. So at PH 7.8 you add a gallon of MA, knock your PH down by .88, and then aerate and wait a few days as your PH drifts up. If you have a few hundred of TA to get rid of it will take you quite a few cycles and many days to get TA down to 80.

TA drops the most when aerating with PH between 7.0 - 7.4. Above 7.6 you will not get much of a TA drop as PH rises. Someplace here I saw a chart that showed the CO2 outgassing that the aeration causes and lowers the TA and the amount relative to PH. If you are not aggressive at lowering the PH to between 7.0 - 7.2 your aeration will not be effective at lowering PH.

I have a SWG running and a waterfall from my spa to pool that gives me natural pool aeration.

So be patient. If you need to lower your TA by 300 it will take about 20 cycles of PH 7.0 - 7.8 and 2 - 3 days/cycle if you had a pool my size.

 

[jblizzle]

How new is the test kit?
If brand new, are you holding the bottle upside down vertically and wiping the tip after each drop so they are fully formed?
Are you swirling the test tube the entire time you are adding drops?
Are you using 10ml of water so each drop is 25 ppm
or 25ml of water so each drop is 10ppm?

 

[capybaras]

How new is the test kit?
If brand new, are you holding the bottle upside down vertically and wiping the tip after each drop so they are fully formed?
Are you swirling the test tube the entire time you are adding drops?
Are you using 10ml of water so each drop is 25 ppm
or 25ml of water so each drop is 10ppm?

Kit is new. I'm doing 25 ml of water, where each drop of R-0009 is 10 ppm.

I'm not wiping, as it never seemed to make a difference (drops are fully formed). I can try it.

- - - Updated - - -

Be more patient. It will take time for the PH to drift up and the TA to decrease.
...
TA drops the most when aerating with PH between 7.0 - 7.4. Above 7.6 you will not get much of a TA drop as PH rises
...

Good tip about the pH range, it's bouncing a bit more than that right now. I'll try to lock it down more to help when I aerate

 

[jblizzle]

The brand new reagent for the TA test can have static build up so the drops are small and almost seem to jump off the tip. Giving false high readings.
But, maybe that is not what you are seeing.

You are swirling a lot right?

Try the 10ml and see what happens ... 1 drop 0007 and 2-3drops of 0008

 

[capybaras]

Ok, I figured it out.

Somehow my R-0009 reagent was bad. I took pool water to a pool store for testing (yeah not that accurate, but a good data point), and TA was ok. I used my neighbors test strips, and TA was ok.

Based on that I ordered new R-0009 reagent. Once that arrived I retested and it is around 100.

So....I guess keep in mind your TFT kit can be wrong!