Yellow leaves - flowering [PICS!]

Hey GC!

So my girl is getting close to finishing up, but lately the leaves are starting to lose all their color! I've been giving it nutrients (a little on the lite side so i don't burn the hell out of them) on a feed, water, water schedule but that doesn't seem to be doing anything about all the discoloration I'm having. I'm fairly sure it's low on N, based off of everything I could find using the search feature but shouldn't keeping it nuted keep that from happening? I'll post some pictures of what I'm talking about so you can see what I'm talking about.

Does the plant just naturally grow old and start killing it's leaves once it gets close to the end? Or am I just not giving her enough of the juice? Or am I dealing with something else all together?

note: i went to take some pics of the leaves and noticed some purple at the tips for the very first time.. not sure if it's really worth noting but i'll upload a pic of that leaf as well


One of the bigger, healthy looking yellow leaves


The purpling leave


Some more yellow leaves, but hard to tell from the bad quality camera/HPS

P.S., I'm growing a UFO seed (from attitude) but not sure which specific strain it is.

 

great! yeah I kept digging around and decided everything was a-okay with them. in fact, i just got my first little taste of her tonight