In order to ensure the pH value of your pool is accurate, calibration of the probe is essential.
Calibrating the pH probe ensures the electrode inside the pH probe has not drifted off or is damaged. Inaccurate pH readings can come from poor calibration, storage, and after the cleaning of a dirty probe.
Poolside Tech offers and provides professional-grade, single-use pH calibration solutions to ensure your readings are consistent and accurate. Our preferred method is a 3-point calibration that achieves the most accurate results.
This 3-point calibration is performed in the following order:
- mid-point pH (using a neutral pH 7.0 buffer solution), then a
- low-point pH (using an acidic pH 4.0 buffer solution), and finally, a
- high-point pH (using an alkaline pH 10.0 buffer solution)
The different calibration solutions ensure you obtain the correct pH values when your pool is circulating water.
We recommend calibrating/recalibrating your pH probe when:
- The pH probe is new
- The pH probe has not been used for a while (ex. in the spring, if your pool was winterized)
- You have recently cleaned the pH probe
- If the results from manually testing the water differ significantly from the reading of the probe
- Annually as a maintenance item
Steps to Calibrate the pH Probe
The steps to calibrate the probe are pretty straightforward – using Installer Mode, select the pH probe you will be calibrating. Press the blue “Calibrate” button to begin.
Before measuring the pH of a solution, always check the buffer/calibration solutions have not been previously opened, are within date, and are fresh!
Press the blue button next to Status and turn it ON.
You will see the current reading from the probe, and options that allow you to:
- Clear the current calibration
- Calibrate Low
- Calibrate Mid
- Calibrate High
If the probe has been previously calibrated, press Clear before beginning the calibration procedure.
Calibrate the Mid Point (pH 7.0) Reading
- Rinse the pH probe well with demineralized, deionized (DO), or reverse osmosis (RO) water.
- Remove the top of the pH 7.0 calibration pouch
- Place the pH probe inside the pouch, and let it sit in the solution until the readings stabilize (this usually takes 1-2 minutes but could take longer)
- Once the pH readings have stabilized, press the Calibrate button for Mid Point (7)
Calibrate the Low Point (ph 4.0) Reading
- Rinse the pH probe before calibrating!
- Open the calibration pouch of the pH 4.0 calibration solution
- Insert the pH probe inside the acidic buffer solution
- Wait for the pH readings to stabilize
- After the pH reading has stabilized, press the Calibrate button for Low Point (4)
Calibrate the High Point (pH 10.0) Reading
- Again, rinse the pH probe
- Open the pouch or bottle of the pH 10 calibration solution
- Place the pH probe inside the pouch and allow the reading displayed to stabilize
- Press the Calibrate button for High Point (10) once the readings have stabilized
As opened calibration solutions are no longer considered accurate after 20 minutes, dispose of any used pouches. You should always use fresh, unused, and unexpired pH buffer solutions for calibration.
When a pH probe reaches the point where it no longer provides accurate readings or is unable to stabilize in the different buffer solutions, it is time for a replacement pH probe.