Yeah. It’s plastic but the metal part of it is attached very precariously. And I don’t have any calibration liquid.
Since Grobo ran out of all the nutrients during the last water change, I can no longer trust the automatic system, so I guess I’ll have to do it manually.
(Bluelab PENCON Conductivity Pen and Digital TDS Meter, Water Tester for Temperature and Nutrient (CF, EC, PPM 500, PPM 700), TDS Testing Kit for Hydroponic System and Indoor Plant Grow):
(Bluelab PENPH pH Pen, Digital Meter for Water with Easy Two Point Calibration and Double Junction Probe Test Kit for Hydroponic System and Indoor Plant Grow, White):