I have been researching on here about ppm and what it should be etc. i got a tds tester from my friend a while ago but they didn't have the instructions with it.(suprise) I've tested bottled water and come out with a reading of 2PPM. My RO Water is also either 1 or 2PPM and tap water is 298PPM. I guess I don't really understand yet what is good or bad and what I do to raise or lower it. I'm growing in soil by the way. Any help or point in the right direction is appreciated
Does it have a label on it? You probably need to calibrate it to be dead on and the calibration solution depends on the make / model of the meter.