yeah, just to be on the safe side. that is a big jump, all of a sudden. The book does say up to 2000ppm which is 3.1 EC on the truncheon, but also states this is most likely too high and can dehydrate your plants...and recommended 800-1200, But I know you can run 1500-1600ppm all day long with mature healthy plants.

I'm running at EC 3.0
that is around 1500ppm,(this is full flower nutes, on the edge, so to speak) if it get's beyond that, I dilute...that is what top-off in hydro is for; To dilute the solution.
I run approximately:
1.4-EC/700-ppm in veg...2.2-EC/1100ppm 1st 2 weeks flower 3.0-/1500 thru heavy bulk flowering, then flush.

A note. I use milwaukee sm301...you have truncheon(I like these also), they convert different. Bear with me and I will try to explain the difference.

OK..Hanna, Milwaukee are converted:
1 MS/CM=500ppm
while the New Zealand Hydro, truncheon meter converts at ratio of,
1 MS/CM=700ppm
so, with your meter 2.15 EC = 1500ppm (approx.)


MS/CM defined is:Milli-siemens per centimeter or
US/CM:Micro siemens per centimeter

PPM testers actually measure EC and convert to PPM*
the 2 scales are not related though
EC equals the specific amount of nutrient solution.
ppm readings are not as accurate, but you can convert EC to ppm's.

Do us a favor; Would you? Measure your solution with your EC setting, note it. Then switch to ppm stting, measure, note it. Post it here. I would like to see if the conversion factors I have are the same as your meter readings.

*loosely from the Indoor bible.

One more Q for U...What set-up are you running? i.e., dwc drip, aero, nft?
I ask because some folks believe you can run higher concentrations of nutes in different systems. lw