Water temps skew results - widely


Gold Supporter
LifeTime Supporter
Nov 29, 2015
Carrollton tx
I tested my pool 2 days ago and the chlorine was 3 parts per million in the pH was perfect. That was from the pool the water temperature was 60 degrees. Tonight I tested the spa which runs with shared pool water the spa was 100 degrees the chlorine was it 9 + parts per million and the pH was off-the-charts high. No changes to the salt water generator or anything else recently is it common for test results to be so different based on water temperature?


TFP Expert
Mar 2, 2011
If the SWG is on while the system is in Spa mode, you can quickly get too much chlorine because the volume of water is so low.

The high pH is likely a false reading due to chlorine affecting the pH color.

Are you using fasdpd to get an exact fc reading?