Alkalinity/PH Input Request

[stshields91]

I have a new pool that was filled late Nov so the plaster ~60days of curing time. I've been dutifully combating what I understand to be expected ph rise with acid and it's worked great. My TA was running at 80 and stable. To try and prevent the constant adding of acid I used the acid/aeration process that also worked well and my TA is now 50. Thise morning my PH read what's pictured below. Two questions for the folks here:

• I read my PH this as 7.5, have a look below at the pic and LMK if you agree or I'm reading it wrong?
• Should I add a bit of baking soda to raise my TA to 60 or 65 which is where I'd like to run it to see if my PH buffers a bit lower? Or should it just give it a bit time? It's been ~48hrs since the last acid add to lower the TA.

Thanks for the help!

 

[Bperry]

I have a new pool that was filled late Nov so the plaster ~60days of curing time. I've been dutifully combating what I understand to be expected ph rise with acid and it's worked great. My TA was running at 80 and stable. To try and prevent the constant adding of acid I used the acid/aeration process that also worked well and my TA is now 50. Thise morning my PH read what's pictured below. Two questions for the folks here:

• I read my PH this as 7.5, have a look below at the pic and LMK if you agree or I'm reading it wrong?
• Should I add a bit of baking soda to raise my TA to 60 or 65 which is where I'd like to run it to see if my PH buffers a bit lower? Or should it just give it a bit time? It's been ~48hrs since the last acid add to lower the TA.

View attachment 552405

View attachment 552406

Thanks for the help!

I’m not sure why you’de want to add baking soda. Your pH will not buffer at a specific value, it’ll just rise a lot slower. Test it again tomorrow and it’ll likely be a bit higher or stable. That’s the goal!

 

[stshields91]

I’m not sure why you’de want to add baking soda. Your pH will not buffer at a specific value, it’ll just rise a lot slower. Test it again tomorrow and it’ll likely be a bit higher or stable. That’s the goal!

Thanks... do y'all agree that my PH is ~7.5 in the pic? Thoughts to increase is to also boost the CSI a bit. it was running comfortably in the middle of the range and is now at the lower limit of what's recommended.

My ph may rise right but the TA should stay at 50 unless i add the baking soda. Just not sure I want to run it that low thus asking for advice

 

[Bperry]

Thanks... do y'all agree that my PH is ~7.5 in the pic? Thoughts to increase is to also boost the CSI a bit. it was running comfortably in the middle of the range and is now at the lower limit of what's recommended.

My ph may rise right but the TA should stay at 50 unless i add the baking soda. Just not sure I want to run it that low thus asking for advice

I’d call it a little higher than 7.5 (just from the photo and my phones screen intensity) but there’s obviously some variance. A TA of 50 is just fine. If the TA drops lower or the pH goes lower maybe then consider adding some baking soda.

 

[stshields91]

I’d call it a little higher than 7.5 (just from the photo and my phones screen intensity) but there’s obviously some variance. A TA of 50 is just fine. If the TA drops lower or the pH goes lower maybe then consider adding some baking soda.

Thanks for the feedback!

 

[Newdude]

Take a thumb from each hand and only compare one value at a time. I find it much easier to say yes/no than play 'best of 3'

 

[pjt]

To try and prevent the constant adding of acid I used the acid/aeration process that also worked well and my TA is now 50.

You normally won't have to make a dedicated effort to reduce TA. Manage the pH and let the TA stabilize where it's happy.

I read my PH this as 7.5, have a look below at the pic and LMK if you agree or I'm reading it wrong?

I like to have a uniform backlighting source, so I hold it up to my monitor with a plain white background (such as Google's homepage). I also find that holding the block sideways or upside down makes it easier to read.

Should I add a bit of baking soda to raise my TA to 60 or 65 which is where I'd like to run it to see if my PH buffers a bit lower?

No, don't add baking soda. TA of 50 is perfectly fine. Don't add MA either. Allow the pH to naturally drift up into the high 7s, where it should stabilize. You should (almost) never need to add baking soda to a non-trichlor pool. What's the TA and CH of your fill water?

Thoughts to increase is to also boost the CSI a bit. it was running comfortably in the middle of the range and is now at the lower limit of what's recommended.

Any pH in the 7s is fine. Let the pH settle in the high 7s, and your CSI will be fine. Upcoming warmer water temperatures will also help.

 

[stshields91]

You normally won't have to make a dedicated effort to reduce TA. Manage the pH and let the TA stabilize where it's happy.


I like to have a uniform backlighting source, so I hold it up to my monitor with a plain white background (such as Google's homepage). I also find that holding the block sideways or upside down makes it easier to read.


No, don't add baking soda. TA of 50 is perfectly fine. Don't add MA either. Allow the pH to naturally drift up into the high 7s, where it should stabilize. You should (almost) never need to add baking soda to a non-trichlor pool. What's the TA and CH of your fill water?


Any pH in the 7s is fine. Let the pH settle in the high 7s, and your CSI will be fine. Upcoming warmer water temperatures will also help.

thanks all of this helps a lot!

 

[wmarq]

I have that same block , came with tf-150 pro kit . I never get a color deeper than the one in that picture. The blocks top color is almost purple @ 8.2 ph and I have never seen that color in the test liquid even when I know I am @ 8.6 ph. IDK probably just me I guess. Anytime it's that color with mine ph could be way higher than you would guess with that block and it's a guess , no other way to say it. The only time im sure with that block is when you are 7.2 and it's obviously a different color. Same way with the chlorine on the other side , 3? 5? really hard to tell the difference and the difference is adding chlorine or not. Seems like there would be a better way idk

 

[Bperry]

I have that same block , came with tf-150 pro kit . I never get a color deeper than the one in that picture. The blocks top color is almost purple @ 8.2 ph and I have never seen that color in the test liquid even when I know I am @ 8.6 ph. IDK probably just me I guess. Anytime it's that color with mine ph could be way higher than you would guess with that block and it's a guess , no other way to say it. The only time im sure with that block is when you are 7.2 and it's obviously a different color. Same way with the chlorine on the other side , 3? 5? really hard to tell the difference and the difference is adding chlorine or not. Seems like there would be a better way idk

There is a better way. The chlorine side of the block isnt accurate and is why TFP suggests using the FAS-DPD test instead.

For pH, how are you confirming the 8.6pH?

 

[wmarq]

There is a better way. The chlorine side of the block isnt accurate and is why TFP suggests using the FAS-DPD test instead.

For pH, how are you confirming the 8.6pH?

I am guessing, here is how. I am currently trying to take my TA to 70 from 150. I bring ph down far enough not to go below 7.2 at a time and wait on it to rise so I can do it again. I take a "guess" at the current ph and put in in the calculator to get a dose of acid for the 7.2 level that I want and when I go back to check it and its 7.2 that tells me I was very close on my guess. I saw that same color in the picture before I ever started and with a TA of 140 at the time I know I was at 8.5-8.6. I had another cheapy old reader and it showed the higher color at the same time. When I initially started I knew that I had a ph that had to be that high so I put in in the calc and the dose brought me down to the 7.2 color exactly .

 

[wmarq]

There is a better way. The chlorine side of the block isnt accurate and is why TFP suggests using the FAS-DPD test instead.

For pH, how are you confirming the 8.6pH?

sorry , im not sure if I should reply to your post directly or straight in the thread. If I did it wrong please correct me , I m new on here

 

[Bperry]

I am guessing, here is how. I am currently trying to take my TA to 70 from 150. I bring ph down far enough not to go below 7.2 at a time and wait on it to rise so I can do it again. I take a "guess" at the current ph and put in in the calculator to get a dose of acid for the 7.2 level that I want and when I go back to check it and its 7.2 that tells me I was very close on my guess. I saw that same color in the picture before I ever started and with a TA of 140 at the time I know I was at 8.5-8.6. I had another cheapy old reader and it showed the higher color at the same time. When I initially started I knew that I had a ph that had to be that high so I put in in the calc and the dose brought me down to the 7.2 color exactly .

So you dont know (its a guess) right?

The pH estimates are just that- estimates. If you read the notes, it says the max amount of pH prediction change accuracy is about .4 and change beyond that is not predictable. If your pH test is telling you the pH is less than 8.2 it most likely is.

 

[wmarq]

lol , yes you are correct it is a guess. but an educated one. Ive been through several rounds of this always being careful not to overdose so I "guessed" lightly and went with the lower dose in the beginning which never brought me to that obviously different color at 7.2. After several rounds you begin to realize that your PH is higher than you are guessing and adjust your guess. The math is not up for guessing I think, the math is the math. If you put a dosage in that should get you from 8.2 to 7.2 and that's where you end up when you are done then your ph had to be 8.2. Im not trying to be argumentative , im just relating my experience so far. I love the test kit, especially that stir block.

 

[Bperry]

If you put a dosage in that should get you from 8.2 to 7.2 and that's where you end up when you are done then your ph had to be 8.2.

Thats not the kind of math this is. Its an approximation thats impossible to calculate with precision in a pool. See the note:

 

[wmarq]

I see that is interesting , thank you. Took another reading tonight , it is darker than the one in the photo above but not 8.2 so my guess will be a range from 7.9 to 8.1 . I guess that s how I need to start thinking about it

 

[Bperry]

I see that is interesting , thank you. Took another reading tonight , it is darker than the one in the photo above but not 8.2 so my guess will be a range from 7.9 to 8.1 . I guess that s how I need to start thinking about it

Yep, just measure “close enough” and if your measurement is technically .1 over or under the actual pH, itll average out over time. I suspect thats why the top of the scale is 8.2. If its over 8.2, you should do something about it. Less than 8.2 and its ok.

 

[Newdude]

I guess that s how I need to start thinking about it

There is high and there is low. If you can narrow it down more than that, GREAT. If not, it's not high, or low.

If you dose a few days too early, your penance is having to dose earlier next time too.

If you dose a few days late, no biggie. PH is a long term concern.

 

[Newdude]

I guess that s how I need to start thinking about it

There is high and there is low. If you can narrow it down more than that, GREAT. If not, it's not high, or low.

If you dose a few days too early, your penance is having to dose earl next time too.

If you dose a few days late, no biggie. PH is a long term concern.

 

[wmarq]

Yep, just measure “close enough” and if your measurement is technically .1 over or under the actual pH, itll average out over time. I suspect thats why the top of the scale is 8.2. If its over 8.2, you should do something about it. Less than 8.2 and its ok.

thanks