PH Problem

[cood60]

Hello all, I have had my pool for 9yrs.
Water balance has been solid and consistent for all these years
On 8/24 I checked TA and noticed it was very low (20 ppm) So I added 180 oz of Baking Soda. Went to 50 ppm
After that the ph and fc were erratic.
The FC went to .5 one day. 128oz of 10% Chlorine
Also added two socks of CYA (I use the powder form in socks to get it in the pool.)
The FC spiked more than expected and the PH as well.
Did an OCLT and it was fine.
I have attached aexcel spreadsheet with log information.
Bottom line is I have been fighting to get the PH to stabalize.
The FC has been high as well, I have been lowering the % every couple of days to get it to stabalize.
I appreciate you all and hope you have some insight. Seems like others on TFP site have had issues with PH but they all say they think it came from high levels of TA, the opposite of my problem

 

[Texas Splash]

I suppose we should address a few things:
- Adding BS to address the low TA was the right thing to do. A TA of 20 was way too low.
- The erratic behavior between increasing the TA from 20 to other things like FC and pH are probably a coincidence. Increasing the TA should have no bearing on FC. The pH may have only been allowed to stay as low as you had it on the spreadsheet because the TA was too low. With a salt pool, you can expect the pH to remain more constant in the upper 7s (7.7-7.8).
- Your Poolmath has no real history, so you might want to start loading your info in there as well. I have a separate spreadsheet for my own personal notes, but I still load all of my tests in PoolMath.
- Neither your spreadsheet or Poolmath seem to show a CYA, so we have no idea where your FC "should" be according to the FC/CYA Levels. With a SWG we could assume your CYA is 70, but you should list it. What you consider to be high may actually not be high at all. In fact, if you had inclement weather and cloud cover, your FC can increase ffom the UV protection. Mine has recently.

So at this point I would recommend you let the pH rise and settle around 7.7-7.8. The TA of 50-60 should allow for that. The FC and CYA are a separate matter, but continue to ensure the FC is balanced to your CYA as noted on the FC/CYA Levels. Of course if an FC is allowed to exceed 10 ppm, it can then influence the pH reading, but I don't think you're at those numbers yet.

 

[cood60]

Thanks Texas Splash. The CYA Column is on the log sheets but I don't check that too often. Sometime I go a month or 2 without checking unless I have had to empty a lot of water due to rain. The second sheet shows the CYA levels. CYA was checked Friday 8/27 at 0-10 and I added CYA immediately but I stopped at 30 Since that is what for many years I kept it at. I will raise to 70 .
Since CYA is at 30 ish, now I guess the FC is close if it stays near 5 or so. I will raise my TA to 50-60 as it keeps fading off from the 60 I had raised it to on 9/5/20.
I did upload to pages of logs did they both show up? I will attach the one with the CYA numbers now in case it did not come through before

 

[Texas Splash]

Gotcha! About the CYA. A min 70 is ideal for many of us SWG owners in the summer. The FC needs that protection. Not sure if you typically close your pool each winter, but you may not need to go all the way to 70 right now if things are cooling off a bit. A CYA of 50 or so might be enough for now with cooler weather and sun angles changing. So just play that by ear depending on how your FC is holding. You can evaluate things and always add more later if needed.

 

[cood60]

Sounds good. I never close my pool, the wife likes looking at it. Agree on the CYA info .
Just a side note, one year I got algae and my CYA was at 80. I sure went through a ton of Chlorine that time to get rid of the algae!
Thanks for all your advice.