I do calmag and ph down, but I generally mix 5gal and have pre-set measuring cup set for 5gal mixing. So easy.
Osmocote Plus, lol. Still loving it, I assume?
That's my thought process over the years as well.
For me, it's the only hydro style I can do in the heat. Hydro in the 80's... not so good. Hempies in the 80's... works all day. Can you imagine a res at 80f+?
Sweet spot, lol. (Yes, I saw the "+.")
Reservoir too hot, no problem - just add DO.
Reservoir too
cold... problem.
DO added by the obvious, of course; either go active or use a reservoir that is small enough to require refilling more often (and then always do so with a
highly-oxygenated mix).
I'd expect that running a reservoir that's too large (IOW, hole too high in container wall) will behave like a soil-grown plant that's allowed to sit around too wet (/waterlogged).
DO is a "thing," just like nitrogen, calcium, et cetera - and needs must be supplied to the plant like everything else that it uses. With fully-passive hydroponics, the grower and the setup must, for best results, do what air pumps (etc.) do in an active setup.