I'm thinking about gettin a hanna 3-1 digital reader. I've been researching and im trying to distinguish between the 3 and when and how to use it. I've read that other readers convert EC to PPM but some seems to be unaccurate? So i was thinking about using the EC reader to test the nute before i feed the plants. I'm still pretty confused on all 3 and how exactly do i use it or what i use it on. If anyone would like to chime in and explain to me. Thanks a lot.