This is a leaf off one of my four plants, she is definitely the weakest of the 4. I had this last round and it affected all plants, lower leaves. It is on one now, but id like to know what it is in case of disease, don't want it to spread. I don't think its root rot, i can see my roots and they are just fine, i don't thinks it a def. of some kind because Ive been very diligent with my nutes. I don't see any bugs, but that doesn't mean they are not there(sneaky lil buggers)
Any help would be greatly appreciated.
Kinda hard to see, but here is a pic, they are quite small the black dots.