I think ur rite on the mark. a little N def beginnin to show, even in flowerin it doesnt hurt to give sum N once a week or so.The purple is not a nute def, but a normal color from its strain. Red n purp mostly from indica strains. Lookin good
I'd let it do it's thing. I can see that some of the tips of leaves in the close up are burnt. This suggests over feeding. You could be using too much of one element and locking out the nitrogen. If I were you I'd drop my PK levels to keep the N in the right ratio RATHER than raising the N to keep up with PK levels that are probably too high. Keep an eye on the pH.
thank you for your help and replys everybody i clipped off all the yellow leaves ...and gave it a 50/50 mix of my veg nutes + bloom nutes
Ill see if it is still spreading or if that took care of it
most of those tips of the leaves are burnt from growing into the cfls when im away rather than over feeding ..im only feeding at half strength recomended because im trying to avoid burning them ..