Can anyone help with a plant problem

Yes I looked for myself but I could not find the answer, I'm still a n00b.
It could be heatstress, lack of light, nitrogen, or potassium from my guesses. I don't know what my soil ph is, but so far I only have used premix packs of miracle grow and bottled water. They have been abused and touched CFL's many times. It seems to be happening in the lower branches in a thickish vegetative canopy. I have lost many fan leaves so far and I hope it won't get any worse.

get some cal mag plus,and u got a little nute burn

Looks like nute burn to me. Ease up on the ferts and should clear up.

Peace

NO miracle grow !that stuff is horrible for growing mj ..even if you dont want to go to the grow shop to get nutrients there are plenty of other options

the plant looks over fed ,probably off balance from the miracle grow ..atleast start using it at a lower strength if you must

so adding cal-mag which is probably needed may or may not resolve the issue,I'd say a couple water feeds and a cal-mag supplement

the damage thats done is done ,but your on the right track long as it does not get worse

Thanks for the advice everybody, I will discontinue feeding for a while and search for cal mag.
Thought that MG was cool in veg but crappy in flower?