Not sure what you mean by runoff plates, but a couple things struck me.
Runoff = 7.0 is on the high side. For soil, you want to get that down to 6.4-6.8. For soilless, like promix, do 6.2-6.6.
Are you letting the soil get a little dry between waterings?
If you suspect salting, a flush will fix that, plus you can adjust the pH of the soil at the same time by running water at pH 6.7 through for your flush. Then feed immediately with a 1/2 strength complete fertilizer, and return to your original feeding schedule after the soil has had a bit of time to dry out from the flush.
stinkyattic Reviewed by stinkyattic on . Leaves kind of down , turning light green H=Answer if you grow hydro or aero C=Answer if you grow coco S=Answer if you grow traditional soil L=Answer if you grow soilless other than coco (Promix, Hyponex, SunshineMix) R=Answer if you grow in RockWool T=Answer if you grow in HydroTon D=Answer if you run any type of automatic drip system, including into soil or soilless = SOIL Rating: 5