Nitrogen or not enough light

The plants are about 5 weeks in autoflower and are flowering.
They look healthy and have been growing.
Recently the bottom leaves on both plants have been turning light green and dying.
They are in 5 gallon air pots with Fox Farm.

Not sure if it is a N deficiency or just not enough light getting to bottom leaves.
Plants:

Some leaves:


Thanks for looking!

hay Swagger hope this helps

It's not uncommon for the bottom leaves to die off in flower to put more energy into the canopy where the light is, looks like u could do some" lolipoping" about now, but pics of whole plant under regular light would help find out the problem better

@emannn2010 Thanks for the picture. Definitely confirms it could be N, but still might be light.
@Bublonichronic Never lollipopped before. I did trim off most of the yellowing leaves today though. Here are some more pics.

hey Swagger, I would imagine you don't have much to worry about but if your still concerned about deficiencies then add a small amount of epsolm salts to your regular feed, it helps the mj take up the nutes oh and I mean a pinch or 2 to 1.5ltr, u could dissolve it first tho in warm water, it helps. good luck and happy growing

Plants will drop leaves that they are not using. If I remember right, the plant recognizes that it is not using co2 and see that as a sign to go ahead and drop the leaf.

With cfl's you'll prbly continue to lose lower leaves as you progress.

How long have the plants been in the fox farm soil... which fox farm? what else have you fed it?

I will definitely look in to using epsolm salt.

Yea a lot of people are saying the lower flowers are lacking in light or are not needed.
Using Ocean Forest and they have been in it since the beginning, no transplanting. They are in 5 gallon smart parts about 4/5 of the way full of soil. I haven't given them anything nute wise.