Leaves turning bright yellow from the bottom up.Wut is this?

Hi fellow RIU's ppl.

Well my plant is almost threw it's 1st week of flowering.And the past 3 or 4 days ive been having a major problem.The leaves on my plant are turning brite yellow from the bottom leaves and is slowly moving to the top.

The leaves that have the discoloration are curling down ward's not up.The problem is getting worse day by day.Its seem to be taking a leaf each day at this rate.They are turning brite yellow except for around the veins in the leaves.After the leave has completly turned yellow it is easy to knock off.I lost a leaf yesterday.At this rate i could lose my plant.And i def. dont want to after making it this far.I think this is a (P) problem?

Does anyone know wut this sounds like?

I have never used nutes yet.But i do have some shultz brand plant food (10-15-10)Do u think maybe i should use like 1/4 strength to see how the plant reacts?

any help woulb be great

thank you

i know but unfortuantly i dont have camera right now.

here are some pix.Does anyone know wuts wrong with this plant?

It looks like a plant using up Nitrogen. That or Lacking of. I need more specifics............

Hank.

nitrogen deficiently, or maybe magnesium. even tho this is your most likely cause I'd still check your ph. start feeding now and you should see improvement in a couple of days. i would recommend foliar feeding to fix it faster.

Yea i never used nutes on this plant,so it is prolly starting to get hungry now.

I feed it for the first time 2 days ago so hopefully it wont get any worse.