what about hydro ? what sort of ec should i be at . about to start my first hydro grow using wilma 4 pot system
Yeah, you're going to have to feel your way around that a bit. I'd also start at half or less concentration...but look at that chart I posted...it has a hydro section & a soil medium section. I'd look at those numbers and start planning from there. If you show signs of deficiency, bump up the numbers until you find a happy place.
Or, here's another way to get at it. Even if you're not using their nutrients, this should help ballpark you. General Hydroponics Trio has a PDF of their most up to date feed schedule online. Look at it and pick the schedule that most fits what you're grow setup is...they have different schedules for aggressive, medium and light situations and they define what those are (hint: they may not be what you think). Once you narrow down which schedule fits your growing situation take a look at the schedule by week. They tell you how what PPM/EC each feeding is. Look at those and start by halving them or less. Match whatever you're using for nutrients' PPM to those numbers.