Why does the WaterGuru SENSE display a different value for TA (Total Alkalinity) than the results from Leslie's?

The Leslie's pool store report does not display TA (Total Alkalinity).  Leslie's reports "Adjusted" Total Alkalinity value. Adjusted Total Alkalinity accounts for the effect of CYA (Cyanuric Acid) in your pool water.  This information is displayed at the bottom of each Leslie's pool water test report: 

• *Total Alkalinity has been adjusted due to the effect of CYA on tested Total Alkalinity

WaterGuru reports True Total Alkalinity, not Adjusted Total Alkalinity.  

To find the True Total Alkalinity, you must perform a calculation. You must add about one-third of the measured CYA back to the adjusted Total Alkalinity reported by Leslie's.

Here is a sample calculation:

• Leslie's Adjusted TA: 75
• CYA Correction: 77 ÷ 3 = ~26
• True TA: 75 + 26 = 101

This result of 101 should align with the TA reported by your WaterGuru device during that same day within ± 20%. 

Note:  Currently we are displaying values which are a 4-day average.  We will be changing the app in an upcoming app release to provide the user with the option to view the actual raw values or continue to view the 4-day average results.