Spa pH problems

[dennisjalbright]

I have a bromine 730 gallon in ground spa. I have an automatic acid feeder that also reads my pH and ORP. My autofeeder pH is reading anywhere from 6.9 to 7.2 but when I test with Taylor chemicals I am upon over 8. I added about 4 OZ of acids to the pool this morning. The chemical pH stayed about the same but the autofeeder reading dropped to 6.6. 5-6 months ago I cleaned the sensors on the autofeeder. This pH difference just started in the last couple of weeks. Any input would be greatly appreciated.

Dennis

 

[chem geek]

Welcome to TFP!

If your bromine level is high then you may be getting a false pH reading in Taylor test. Try temporarily lowering the bromine level to 6 ppm or lower and see what happens with the pH test. If they are still different, then your pH sensor may need cleaning and re-calibration. pH and ORP sensors are finicky and need regular maintenance.