Ph + ta

[93specv]

New to this forum, new to pool maintenance...

...I started caring for my in-laws pool with baquicil this summer. This was their idea from last year. Long story short, I found you all and I converted them (mentally then physically) to the TFP methods. Baquicil gone, sand changed, FC/TC/CC levels now balancing out nicely and water is crystal clear! TYVM!!!!!!

My troubles now seem to rest with balancing TA and PH. It seems ones up and ones down and vise versa. Raising TA to help maintain PH then raises PH which needs to come down which drops TA, seems no win. Then no matter what, aeration kicks it in the butt regardless. Am I missing something or just overcomplicating it?

TIA

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I will mention that it has been SUPER uncharacteristicly warm here in the north east, 90's+ for weeks without rain. I know that is factor.

 

[Mr Bruce]

I assume this is not a SWG pool. Are there waterfalls or other water features? Can we get a full test with results?

 

[atttech-2]

You did not mention any specific values you are trying to hit but my thought is you may be focusing on the TA a bit too much.

My pool for instance seems to like a TA at around 60 to 70 which by many guidelines is low but if I keep my pH around 7.6 to 7.7 that is just where my TA ends up. I bump the TA up once in a while but it does not seem to change the acid demand and will just fall with in a week or two so for the most part I just ignore it.

Do you know what the CSI is? As Bruce said full set of numbers would be good

 

[93specv]

Sorry, no. This is fresh water. No waterfalls or add-ons but only aeration from the minimals-pool use and filtration...rain if it'll ever occur.

TC- 3
FC- 3
PH- 7.8
TA- 70
CYA- 35

This is from the morning test not long ago. Ph was nice in the sweet spot last night at 7.5 but as expected, it's now up from the TA increase. TA was at 40 last night. Pool math suggested roughly 15lb of baking soda to get to 100. I added incrimentally about half that. TA is up as expected but with PH up too, I fear it'll swing higher with further attempts to raise TA to 100.

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Am I confused with mixing ideas? My understanding is that much like CYA helps maintain FC levels, TA helps maintain ph levels. No?

 

[Mr Bruce]

I think you are chasing your tail. Don't bother adjusting TA unless it gets below 50. Don't lower pH until it gets above 7.8. You may get to a sweet spot where pH is 7.6-7.8 and TA is 50-60.

 

[tim5055]

First, you are basing your changes on an error. You said "Raising TA to help maintain PH". Raising TA makes pH more unstable. LOWERING TA lessens pH swing to a point. The pool industry seems to like TA around 100 but in our experience that is usually too high.

Now, every pool is different but most seem to like TA 70ish. Mine like sit in the 50-60 range.

Stop chasing a "perfect" TA number and let the pool decide where it wants to go. Just adjust pH for. Few weeks and see what happens.

 

[93specv]

All sounds good to me. These early stages I've been making notes and keeping track of changes to further learn what reacts to what and how.

But tim, I'm only basing my info and explanations on the Info provided here at TFP. Right in the pool school ABC's, the TA definition says that a lower TA will swing ph wildly. Did I read that wrong?

Pool School - ABCs of Pool Water Chemistry

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"At low TA levels, the PH tends to swing around wildly. At high TA levels, the PH tends to drift up."