Temperature readings inaccurate, why?

Ensure that your calibration solution is at the same temperature as your growing environment before you calibrate your pH tools. Read below for tips on how to get accurate temperature readings.

Temperature affects the calibration process of your pH probe. pH is temperature-sensitive, so the temperature of your calibration solution affects the accuracy of your reading.

Here are some tips for calibrating in winter:
• For Bluelab Combo Meters: When calibrating, the temperature of calibration solutions can be cold. Place the EC Probe in the solution along with the pH Probe for 5 minutes to stabilise the Automatic Temperature Compensation (ATC).

• For Bluelab Pens: Before you calibrate, leave the sensor submerged in the calibration solution for 5 minutes. This is so the pen adjusts to the temperature of the calibration solution and gives you a more accurate reading.

What to do if your calibration solution freezes:
Temperature will affect the measurement of pH, but not the composition of solutions. If a calibration solution sachet freezes, let it thaw, come back up to the temperature of your growing environment and proceed with calibrating your pH.

For calibration solution bottles and sachets, do not pour out a sample while there is still an ice block in the middle. Why? - There may be differential freezing rates, for example the ice-block is made up of water, and the unfrozen solution could be higher in salts due to evaporation. Shaking up the bottle may help solve this, in the event of freezing.

On the other extreme, if you have had calibration solution sitting out in the hot sun, or in a hot car, allow it to cool back down to room temperature.