TFP Recommended TA account for CYA?

[Gollie]

I love the TFP method and community but this is something that has always bothered me. It's not clear whether or not the TFP recommend TA range accounts for CYA. I have searched through every resource I thought could possibly be related and haven't even found mention of how CYA accounts for a portion of the TA reading. It seems like a MAJOR oversight for what is otherwise a quite thorough knowledge base.

1. Does anyone know definitely if the TA recommended levels accounts for CYA? For example, the pool math app says ideal recommended range is 60-80 for TA. If I test TA and the result is 90 PPM and just go off of that, then I'd think it was too high. If I account for CYA though, then I'd still be in range.
TA-(CYA x PH factor)=TAadj
Example: 90-(40 x 0.34)=76.4
[in this example, PH is 7.7 so the corresponding PH factor is 0.34. If PH were 7.6, it'd be 0.33 or if it were 7.8 it'd be 0.35]

2. Is there a way to contact site owners/mods (whoever writes/edits the articles) to discuss the ommission of this info?

I know that "You do not need to lower TA just to reach a target number." My PH keeps rising quickly though (no water features), so I know I need to get my TA down to better stabilize my PH. I have been using the calculated TA adjusted number because it's a more accurate/true reflection of the actual TA level. If the TFP recommended range is using the basic TA readings (that do not exclude the effect CYA has on those readings), that makes a significant difference.

Thanks!

 

[ajw22]

We do not use adjusted TA. PoolMath makes any necessary adjustments in its calculations.

TA - Further Reading

www.troublefreepool.com

 

[Bperry]

I love the TFP method and community but this is something that has always bothered me. It's not clear whether or not the TFP recommend TA range accounts for CYA. I have searched through every resource I thought could possibly be related and haven't even found mention of how CYA accounts for a portion of the TA reading. It seems like a MAJOR oversight for what is otherwise a quite thorough knowledge base.

1. Does anyone know definitely if the TA recommended levels accounts for CYA? For example, the pool math app says ideal recommended range is 60-80 for TA. If I test TA and the result is 90 PPM and just go off of that, then I'd think it was too high. If I account for CYA though, then I'd still be in range.
TA-(CYA x PH factor)=TAadj
Example: 90-(40 x 0.34)=76.4
[in this example, PH is 7.7 so the corresponding PH factor is 0.34. If PH were 7.6, it'd be 0.33 or if it were 7.8 it'd be 0.35]

2. Is there a way to contact site owners/mods (whoever writes/edits the articles) to discuss the ommission of this info?

I know that "You do not need to lower TA just to reach a target number." My PH keeps rising quickly though (no water features), so I know I need to get my TA down to better stabilize my PH. I have been using the calculated TA adjusted number because it's a more accurate/true reflection of the actual TA level. If the TFP recommended range is using the basic TA readings (that do not exclude the effect CYA has on those readings), that makes a significant difference.

Thanks!

TA is TA. The thing you’re trying to calculate is “adjusted TA” which is not useful for anything except to get you to buy baking soda.

 

[JoyfulNoise]

I have been using the calculated TA adjusted number because it's a more accurate/true reflection of the actual TA level. If the TFP recommended range is using the basic TA readings (that do not exclude the effect CYA has on those readings), that makes a significant difference.

This statement is really not accurate. There is no “true reflection” here. Total alkalinity is just that - the sum total of ALL chemical species that affect the ability of the water to exchange a proton (H+) which is the measure of pH. Every alkaline species - carbonates, cyanurates, borates, etc, contributes a certain amount of buffering effect to the water that is depended on the molar contraction of the species and its buffering capacity. So in relation to pH changes, it’s the TA that matters. The only time one needs to use adjusted alkalinity, which is basically carbonate alkalinity, is when one needs to calculate a saturation index based on calcium carbonate equilibrium (CSI is used in PoolMath). Other than that, there is no other reason to use adjusted alkalinity. As such, TFP calculates adjusted alkalinity in the background so the pool owner doesn’t have to bother with it.

 

[Gollie]

This statement is really not accurate. There is no “true reflection” here. Total alkalinity is just that - the sum total of ALL chemical species that affect the ability of the water to exchange a proton (H+) which is the measure of pH. Every alkaline species - carbonates, cyanurates, borates, etc, contributes a certain amount of buffering effect to the water that is depended on the molar contraction of the species and its buffering capacity. So in relation to pH changes, it’s the TA that matters. The only time one needs to use adjusted alkalinity, which is basically carbonate alkalinity, is when one needs to calculate a saturation index based on calcium carbonate equilibrium (CSI is used in PoolMath). Other than that, there is no other reason to use adjusted alkalinity. As such, TFP calculates adjusted alkalinity in the background so the pool owner doesn’t have to bother with it.

Thank you! I love answers like this that give "the why" and science behind things. I have trouble accepting "that's just the way it is" types of replies, so this is really excellent!

 

[Gollie]

TA is TA. The thing you’re trying to calculate is “adjusted TA” which is not useful for anything except to get you to buy baking soda.

I think I might omit "trying" (since I was successfully calculating, not simply just attempting) and I do believe I referred to it as "adjusted TA," but otherwise, thank you for the informative reply!

 

[Gollie]

We do not use adjusted TA. PoolMath makes any necessary adjustments in its calculations.

TA - Further Reading

www.troublefreepool.com

OMG THANK YOU!

1. Super excited I can save myself a few extra seconds not having to calculate this every day anymore!

2. I'm not sure I would have ever found this (and I have cumulatively spent at least a few hours combing through TFP articles periodically over the past year-ish to find this answer). I've bookmarked it so I can reference in the future too. There's so much helpful info, and I love learning all the "deep end" details of pool chemistry and maintenance!

3. Now I really want to set up a second (fake) pool in the app to play around and see how different numbers logged in the test results affect recommended chem addition values haha.

4. Interestingly, I use the Taylor K-2006 kit and it was in the corresponding booklet that I first learned adjusted TA was even a thing.

 

[PhoenixTim]

Thank you, Gollie, for that question as that was something I was wondering about too.

 

[Newdude]

I have cumulatively spent at least a few hours combing through TFP articles periodically over the past year-ish to find this answer

In the left sidebar or towards the bottom of any forum page is the TFP Wiki. If you have a random thought, it's likely well covered there and easy to find in alphabetical order.

Read through anything relevant to you in your spare time. Many of the deeper discussions will make more sense now versus the information overload of being new back when.