Hi Dana.
By my looks off things your plant looks healthy at the moment. Probably starting slight Nute Deficiency.
I only think you don't use enough nutrition at the moment by looking what you have shared in your diary.
Very slight at the moment but for my view you should Use some kind off Bloom nutrition At this stage and stop Root nutrition and add a little Grow.
I can see the Lower leaves getting purple ( don't see on pictures ) But because the plant is taking up nutrition from the oldest leaves it grow.
(Use) Grow and Bloom nutrition Solution For next 3weeks.
After that stop Grow Nutes and feed only Bloom till 2/3 weeks before flushing.
Will recommend to remove a few leaves covering lower bud sites. To Open light penetration to lower buds and leaves.
Good luck and hope this helps.