Aqua Master: Substrate EC/Temp E300 Pro Exclusive to Global Air Supplies, the E300 Pro is the ideal meter to measure the EC and temperature of coconut soil and other moist, soft substrates and liquids. The E300 Pro features a modern and robust housing, with easy to operate buttons. It also includes an EC electrode of unprecedented quality. The meter is delivered fully calibrated and includes batteries. Now with: Calibration indicator 2 decimal places AAA batteries How does the meter work? Connect the PIN connector of the electrode to the EC meter. Rinse the electrode with running water and dry it using clean kitchen paper. Press the on/off button to turn on the meter. Place the electrode in the (soft) substrate (make sure the substrate is well wet/damp, otherwise the meter will not work properly) or liquid to be measured. Wait for the value to stabilise. The measurement is now complete. Press the HOLD button to save the measurement. Do not forget to press the HOLD button again when the meter is used once more. Rinse the electrode with clean water after use, so that no residue is left on the electrode. Press the on/off button to turn off the meter. Aqua Master Replacement EC Electrode E300 Pro This is the replacement probe for the Aqua Master Substrate EC/Temp E300 Pro. For instructions on how to replace the electrode, please refer to the user manual for the: Aqua Master Substrate EC/Temp E300 Pro. Replacing the electrode: Detach the PIN connector of the old EC electrode from the meter. Connect the PIN connector of the new EC electrode to the meter. Calibrate the meter as described in this manual. The meter is now ready for use.