Gelato

EC is a better reading them PPM. PPM can be used on a 500/640/700 scale meaning that 500ppm or 640ppm or 700ppm can all equal 1EC. 1EC is always 1EC no mater the meter. its simple to use plug it in the nutrient solution and hit read. can also be used to read runoff water of pot if you water till runoff. Its great as a diagnostic tool to confirm numbers and make sure it not to weak or strong. The device should come with a manual but also youtube has some good how to videos. Best Of Luck!