my leaves are turning BLACK! HELP please

ok I've been looking for a solution to this by looking at other threads and pictures and just cant seem to find anything that looks like this.

This is obviously an auto that is being grown in miracle grow seed starting soil, and under a 68 watt cfl and two 26 watt cfl's. The plant itself is about six weeks old so it doesnt have much time left. after about 3 weeks in I started it on fox farm nutes at 1/4 strength. I noticed some of the lower leaves started dieing so I stopped the nutes all together.

Right after I stopped the nutes I started noticing these spots of my leaves, I figured whatever the plant looks good I'll let it go. It's getting worse FAST, the worst leaves are EXTREMELY dry and if I try to bend them at all they crack. I flushed it yesterday and havent seen an improvement yet.

Any help would be greatly appreciated. Thank you

Looks like a rash man, keep flushing it id say.

looks like normal wear&tare

Looks like calcium deficiency.

You answered your own question. You were lightly feeding and stopped and now the problem is worse. Try a half strength feed or even 3/4 strength feed.

here are the most recent pictures taken minutes ago. I started adding fox farms grow big to my water because it is high in nitrogen which I am hoping was my problem. The blackness seems to have slowed down spreading.