Desperate need of some help

Hey guys, Looking for a little help here. First time grower and had up until about 2 weeks ago a really healthy looking bunch of plants. Then I started noticing brown spots on the leaves. Now I am at a point where the leaves are dry and curling, turning yellow in a major way. Oak blue strain 4 weeks into flower, had a bit of a mite problem but thought I took care of em. Used FFOF soil, Nutes are Guano, Molasses, Vita Grow Part C, Seaweed. Here is a pic of what they look like now. Any info would be appreciated. Thanks.

Are you sure they aren't red spots?

Yeah Im pretty sure. They almost looked like maybe they were burn marks. But they started showing up in all the plants in different areas. Then spread over the whole leaf.

If I had to fashion a guess... I'd say cal-mag, thats how my cal-mag problem looked

With hps on its hard to tell. But it looks like all the fan leaf stems are full purple, and you're fan leaf is dieing out from edge to center vein.
If this is the case then your plant is not takin' up any food. So you have a lockout. My 1st guess is ph, what is your feed ph? The other is a cal deficiency, but in soil it's unlikely unless you are usine RO or distilled water.

Need more info.

I just assume it is whatever the OP didn't consider... pH,,,, or it's allergic to cops. lololol onetime

You have a choice either let them be and keep water/feeding them intill there ready to chop or try and resolve the issues and risk killing them completely. I'd go with one, harvest and do something different next time. Experience is key

Looks like a potassium def.
Not 100% sure.

Sir KK