Measuring & calibration for your grow room

Choose the medium before the meter

A liquid meter tests a different sample from a direct substrate probe. Decide whether you need to check nutrient solution, runoff, substrate or air. For pH and EC, choose between separate meters, a handheld combo pen and a combo meter with separate probes. The P110 Pro is a pen; the P700 Pro2 has a separate display unit and connected electrodes. Consider how you take readings, where you read the display and how you maintain the probes.

Read the unit with every value

EC is often expressed in mS/cm or µS/cm: 1 mS/cm equals 1000 µS/cm. A ppm display uses a conversion factor, so readings on two meters are not automatically equivalent. Extra decimal places also do not prove a smaller measurement error. Compare range, resolution and accuracy separately.

Calibration, checks and storage serve different purposes

Calibration adjusts the meter against a reference. A check reading shows whether the display still agrees with that reference. Storage solution protects electrodes designed for wet storage. Pour a small amount of reference solution into a clean container and never return used liquid to the bottle. Match care to the exact electrode type: a dry storage electrode needs a different approach from a Bluelab pH probe.

Use measurements to make specific adjustments

Record the time, position, unit and conditions. Compare temperature and humidity during light and dark periods. A separate sensor does not control equipment on its own; automatic control needs a suitable controller and connections. Use a suitable measuring jug for dosing and recheck the solution after mixing thoroughly.

pH & EC meters · Calibration solutions · Measuring jugs

Which meters do you need for water, substrate and air? · Calibrating a pH meter and storing its electrode · EC, mS/cm, µS/cm and ppm: compare readings correctly