Nitrogen deficiency and??

the first 2 pics show a plant with yellowing leaves I assume this is just a N deficiency. I managed to get my hands on some Earth Juice Micro-Nutes and Earth Juice Grow, would a weak dose of these be sufficient or should I find a higher N type supplement? if so what would be a good brand.

The 3rd pic shows what im thinking is a Mag deficiency?

There is about 30 of these plants in 2 gal gro bags mixed with perlite and fox farm ocean forest. Some are being effected and others not, as there are 2 diff strains working here.

Thanks for any input people!
:rasta:

You're right, not just N.
I don't see that Mg def is in the top 3 obvious problems.
Iron and N def go hand in hand and a foliar feed is in order. I have had good luck with Iron Green, a N + Fe lawn foliar, lol!
I am also seeing necrotic spots in pic 3 that my first hunch is to say K problems. But your nutrient load there is so obviously WAY out of whack that you really need to flush out and start from scratch:

Overall, what I get from these pics is a plant that is having nutrient uptake problems... what is your pH? What have you been feeding it, how strong, and is flushing part of your routine?

It is very difficult to make a good diagnosis without that info.