This plant is very sensitive to nutrient and PH changes. I raised the PH to 6.4-6.5 because I was noticing some calcium deficiency on one of the leaves. I also changed the feeding shcehedule to 1/2 micro, 1/4 gro, and 1 1/2 bloom. There was an over night reaction with the lower leaves starting to yellow.
I will go back to my original Mid bloom feed 1 micro, 1/2 gro, 1 1/2 bloom at 6.0 PH. It seems to be what the plant likes best at this stage.