Yellowing and drying out of leaves

This is my second run through with this strain (Critical Hog) and both times in mid to late flowering I have observed this changing of leaves. I have been uping my phosphate and nitrogen to see if that would help but it seems to stay. I have also turned my fan on higher and raised the light thinking it might be the heat from my hps. Any ideas on what it could be? I am between phosphate deficiency and nitrogen deficiency. Currently using the Lucas Formula, tweaked a little.

Here are some pictures,
Thanks for any help

your totally fine.....this is supposed to happen during late flower...this just means your close to harvest! most strains do this naturally. if this is happening before week 5 of flower then you might have a deficiency.

what kind of explanations "plant supposed to die in flowering..." remember, healthy leaves, bigger buds. if you fail to keep them healthy green till the harvest, you will yield less.

leaves look very dark green, which probably indicates that you have too much of N. adding P indoors is not necessary, since it's very rare thing to have P def. Unless you are overfeeding with something that causes lockout. upper part leaves have burned tips. thats a sign of overfert. with overfert you can cause ca, mg lockout which could result in what you have.

so firstly. what nutes are you using and at what quantities.
do you have pictures of lower part of plant? since N, P, K, Mg problems first appear on the bottom.
what soil are you using?

also save this chart somewhere in bookmarks. you will need to get back to that page and read and reread until you will get used to.

not get back here and post some more details man. plant needs help

Ok so I am doing a hydro bubble bucket setup. I am using the GH flora series micro and bloom. 8.75mg micro and 16.75 bloom per gallon. I started at 8/16 like the lucas forumla says but i started to see some change to the yellow and decided to up the nutes a bit to see if it would fix the discoloration, thats why its .75mg higher a gallon.

The lower growth looks fine to me, it is a scrog setup so the lower branches are under the netting.

Think its over feeding at this point? By adding more I just added to the problem?

Here are some more pictures of smaller buds lower on the plant and around the top some more.

Leaves will turn yellow during the last stages of flowering.

Ya it did this same thing last run and it really didn't affect the end result, I just don't know if its a issue or just how it grows. It is mostly just the larger fan leaves, after a while it will start to go purple and dry up. Check my previous grow log in my sig to see how that plant looks similar.