|HM Digital COM-80 EC meter|
This meter can measure the electrical conductivity (EC), total dissolved solids (TDS) and the water temperature. It can measure EC in µS and mS, TDS in ppm and ppt. Fancy. I hope I don't have to care about all of this. I found a chart of different desired ppm levels for different plants so this is the only measurement I care about at the moment.
|Measuring the ppm of the nutrient water|