Yeah man all you can do is go over every variable and make sure everything is in check,I know the air exchange really made a difference on my plants.What i was noticing is on days i was in there alot with the door open they were looking better than on days where it was closed up more.After i did the actual air exchanges they really improved.
I think some times we luck up on some grows where our environment doesnt lack anyhting like my old setup the humidity was always high.I never gave a shit about it cause the plants always looked lush.Plenty of air exchange,high humidity in veg everything was great,
Being in a whole new setup those phantom issues come up even though we still grow as good as we ever had,Nothing changed but environment.It really makes you look into everything.
In RDWC i can control every part of the root zone.Nothing in the mix will be out of place so when i have issues its easier to know what the problem is,