i have a bit of kelp in my nute bottles. GH floranova.
that won’t show up accurately as ppm/ec, correct?
just wondering if the ppm number should be lower than a typical non-kelp nute solution? lots of ways to calibrate, but i was just wondering generally if those types of nutes reall don’t need such high ppm?
EC / electrical conductivity is increased by the separation of anions and cations in the nutrient solution. As growers, we are really interested in TDS (total dissolved solids). This is only approximated by EC, and not a direct measurement.
EC is influenced by temperature (why temperature compensation is used), but also the kind of dissolved matter. Salts separate into ionic components (cations and anions) easily and completely, but organic compounds do not. And they often require other means to break down (bacterial, enzymatic etc). So EC is likely not going to be an accurate reading of TDS, and I don’t think it is useful in that case.
that is what i thought. i posted a while back about having issues using high ppm on my tds/ec meter. however, i always have some organic content in my nute solution. it smells really bad, like rotting fish and poop. i thought i read that the ec is really just mostly reading the Ca content…but i am not good enough at chemistry to know on my own.
so, i use the ppm to indicate how much i put in on a relative basis from feed to feed since i always use this kind of nutes, but I haven’t found it to be more indicative than that. maybe my 500ppm is 800 on someone else’s nute regime.