well your not doing it right then , if you flush with straight RO you can actually learn a lot about what is going on and I’m talking about doing this for 2-10 hours depending on what kind of nute lockout situation you have but the point of this is so you can read your run off in a hydro system PH tells a lot about what the plants are doing ...
you talk about lockout, thats exactly what i try to explain to rky .. but he dont want to listen
if you have lockout thats because fertilizer dryout and accumulate in your medium ... and the cause of this is not enough runoff
at the end you don't know what is in your medium .. nor the ph in the rootzone
because doing rockwool/coco.. hydroponically with small runoff is a recipe for failure
people will feed light to counteract this, but its far from optimal
i did for years so i can talk
now i feed every 2 hours with large runoff and everytime i do, the large drain rinse the medium so i keep my rootzone at the same ph/ec of my feed
it's normal for rootzone ph/ec to fluctuate between feeds .. but it must be "reset" everytime you feed
doing this your plants will grow crazy fast because you replenish the solution/oxygen often, and keep the ph/ec very stable.. so you will need to feed at high EC, between 2.5 in veg to 3.0 in flower
i use co2 (propane), sealed environnement