Balancing TA level after a refill

[Zuli]

Due to a pump outage that lasted 10 days, my pool became a pond.I've tried to SLAM it, but CYA went to high (100) and I had to drain and refill.
Starting values after refill were:
FC 1.4
ph 7.5
TA 145
CYA 50
I've raised the FC with bleach 15%, and then I've started to lower the TA. My first shot has been to reduce TA by 20, so I've added 4,7L of Muriatic Acid.
After that, surprisingly, pH was 7.0, but TA was 153! Checked three times!
So, either the starting measure was completely wrong, or something strange happened. Do you have suggestions?
What should I do now?

My measure kit is the Lovibond Scuba II photometer.
Pool is 94,000 L , vinyl.

 

[cowboycasey]

Welcome to TFP

Those photometer we just do not trust, some are closer than others.. they kind of work.. I know you can have a hard time finding a Taylor K-2006C but that is really what you need to follow TFP..

With that said do not worry about TA, it will go down when you drop PH.. A higher TA will raise your PH faster and therefore it will lower TA faster...

If your CYA is actually 50 your FC is way to low..FC/CYA Levels You may need to SLAM Process but to see if you need to do an Overnight Chlorine Loss Test to see..

 

[Zuli]

Thank you!
Yes, it is almost impossible to find the Taylor here in Europe
Regarding the FC. Now is 3.4. Should I prioritise FC over TA? Right now I'm aerating to get the PH back to 7.6 and then drop again 7,6L of muriatic to get to TA = 100. If it works

 

[mknauss]

Focus on FC. TA is of little consequence to your pool water chemistry with a vinyl liner pool.