Understanding PPM, TDS, and EC and how it affects your grow

Just bought a new meter an i

'm new to PPM, TDS, and EC I’m aware they are all about the same thing that they are the amount of nutrients in your solution just different meanings. But what I’m having issues with is scaling the nutrients to the right rates. I know its a lot of trial and error but I wasn’t sure if someone could give me a good starting point. I’ve tried using measurements for 4.5 gal in a 5 gal container full and still measuring around 1940-1970 ppm. Also I’ve heard from other growers anythinfover 2k ppm is overkill yet week 8 on this schedule specifically calls for over a 2k range

Discussion of EC has to happen in the context of grow medium and watering/fertigation method.

Your pen has the option for 500 scale and 700 scale for ppm. You’ll need to see what yours is set on. The schedule you posted is on the 700 scale. This is adjusted for 500 scale meters


I’m growing in coco coir 70/30 perlite mix with fox farm trio nutrients, Epsom salt, molasses, floranectar and cal mag also using RO water