ever noticed that the range for most meters is
something like
rararararararaar hahaha
EC : 0.00~19.99EC
CF : 0.0~199.9CF
TDS : 10~19990ppm
notice how they are all just log10 of each othererersrsssr raraarrar!
from my understanding, these readings are calibrated to a NaCl ussually 700ppm or 431ppm etc.
Ive seen calibration solutions for EC and TDS.. But wouldnt they have to be standarised solutions of the same nutrients present in our ferts to be accurate calibrations? and seeing as we all have diff ferts that would mean we would have to all have individual calibration solutions...