I would say if your plants were doing fine a week ago then back track to that setup and slowly start making changes so you can see what happened.

They don't look droopy to indicate that they are drowning.

Still looks like a deficiency of some sort to me.

edit: again I'm not great at troubleshooting problems, but I never will be unless I try right? Hopefully some pro comes in here with an answer/explanation.
daihashi Reviewed by daihashi on . Ebb and flow problem...why are my plants turning yellow? (merged) Can any one answer this...it seems pretty simple but cant seem to get anything in plant problems to match ...i keep having a problem when i switch from one growth stage to the next ...i had ak47 and burmese kush plants in 4x4x4 rock wool cubes which i watered daily by hand with a basic flora nova grow and hygrozyme nutriernt mix the plants flourished ..i did this for almost 7 weeks and was able to sex out the true males...i then took my remaining females and put those into a 4'x4' ebb and flow Rating: 5