hey sandorv, well , it's my understanding that the EC reading is a useful proxy for where you stand with regards to the feed, but it's not an exact reading because different nutrients and additives are of a different quality with regards to EC. In other words NPK is really "dangerous" EC, too high and you get a burn CalMag is "friendly" EC like you can actually put quite a lot of it without harming the plant . I would take my EC measurements without micronutrients then add whatever quantity micro your plant does need beyond that with my eyes closed (obviously dont over do it, but i trust your judgement) . Hope this helps ! 🚀