Yellowing leaves (Week 4 flowering)?????

[Prob034]

Hello...I currently have a couple gems going right now (2 grape ape strains, and 2 ak strains). This morning I noticed that on one of my grape ape plants the leaves are slowly turning yellow from the bottom up. It doesn't seem to be affecting anything but the fan leaves. The plants are at day 24 of flowering.
I've done a lot of reading, and quite a few places say its pretty normal for fan leaves to yellow up during the later flowering stages, but I'm a little concerned thou because it doesn't seem that far into flowering for them to be turning this soon. None of the hairs have began to change and there's very little weight in the buds yet. I figure I have at least four weeks left, probably longer for the AK strains. Just wondering if it could be a Mg deficiency, and should I go into panic mode or ride it out and see what unfolds. Thanks everyone ahead of time for your help.
*(you can see it well in the first pic. Leaf in middle in back)*

[Charbud]

Are you feeding them nutrients ? Your ph ?

Your ph could be off to they have nute lock which will stop the roots uptaking nutrients and using the leaves as food.

You might not be feeding them any nutes at all.

They may just need a little mid flower NPK dose - nitrogen def.

C

[OldHead09]

What medium are you using...looks like a nutrient lacking..feed it gently and see how it responds...

[WashougalWonder]

I think this is normal, but I have never watched an AK47 flower...soon I hope.

You could, if you must, give a very small amount of a well balanced nute formula, with lower N and higher P&K levels...like 2-4-5 or so....not set in stone. I, myself would not nute that plant. Maybe some unsulphered molasses. I put a dollop, about a teaspoon, in a gallon.

Right now the plant is putting everything it has into flowering. It does not need the sun leaves as much now, especially the low ones not really getting enough light. Eventually on some species all the fan leaves will turn very yellow and the buds will be green. It is nature's way of saving energy and being energy efficient.

[OldHead09]

Are you feeding them nutrients ? Your ph ?

Your ph could be off to they have nute lock which will stop the roots uptaking nutrients and using the leaves as food.

You might not be feeding them any nutes at all.

They may just need a little mid flower NPK dose - nitrogen def.

C
I think a PH fluctuation would show more deficincies as well as the typical claw leaf look....IMO

[Charbud]

I think a PH fluctuation would show more deficincies as well as the typical claw leaf look....IMO

lock not burn