could anyone give me a rough idea of what ec is in ppm please? i'm on a budget and could only afford an e-bay tds meter which is in ppm
EC is a measure of Electrical Conductivity from two probes 1cm apart. 1 EC is = 1 microsiemens, EC can be converted to PPM by multiplying by 500. PPM can be converted to EC by dividing by 500. The above info was taken from http://www.octiva.net/projects/ppm/ Here is a simple guide but it's not that easy to make out. http://www.hydroponics.net/learn/debate_over_ec_and_tds.asp