Wisteria is a real K hog. Also this -
Unless you are truly trying to figure out why and the process is important to you, why not just supply nutrients at a non-limiting amount(ie estimative index dosing) and take all the guess work out of it. If you continue seeing high nitrates then stop dosing kno3 and up your k2so4 dosing.
I'm definitely still learning and so the knowledge is important to me.
What I'm looking for is a long term balance where the plants and waste offset (mostly) and I can go very long without water changes (a month or more).
As I understand EI, it counts on weekly water changes. I get it, understand that is in some ways better, but ... I don't want to.
I guess (from the little reading I've done) it is more like Tom Barr's "low tech non-co2" method. Except I am adding excel, at least until I get fully grown in. But whatever you call it, and perhaps not for really good reasons (that is what I am trying to understand) I am still trying to get about the "right" amount of nutrients, so as not to be limiting, to err a bit on the high side, but not to build up too much either.
But yes... knowledge is important to me.