This is most likely a fungus. Couldnt tell without pics. But most of all dont take this advice. Dont overfeed your plants!!! You cant undo an overfeedinng but you can always correct an underfeeding. Look at the plants and they will tell you what they need. Saggy leaves & dry soil = needs water. Yellowing leaves = need nitrogen. Dont burn your plants then cut it back, most strains will florish with only 1/4 strength nutes through the whole cycle. Not to say dont use more, but dont use too much.
Dont tell people what to do. State your opinion, but dont bag on me because you are retarded.
Over fertilization can be EASILY corrected with a flush or heavy watering with no nutes. Burning a shade leaf or two will not harm the flowering part of the plant. I never said burn off half the plant then cut it back. sheesh!
I have grown for 30 years and have done many side by side tests. Feeding a plant as much nutrients as it can take allows the plant to reach maximum potential. We once fed 3 clones one light, one as recommended and one we pushed the hell out of. The third palnt yielded more than double what the first one did. Yes, there were some sorry looking large leaves on the plant, but I dont smoke leaves. And the buds were awesome. Grow up and try to realize you dont know everything.
Yes a plant can "flourish" on 1/4 strength, but it sure as heck can't reach its max potential. Isnt that what this forum is all about? Trying to get the best yield you can?
If you dont like to take risks, sure play it safe and use 1/4. Sometimes I use 3 times the recommended dose. It depends on many factors. Example bubbakush kept sucking up nutes. I was up to 2 tablespoons of cha-ching every other day. I thought surely I would see some burn. nope. soil test revealed low nutes. Next day 3 tablespoons and each day after. On day 3 they started to show signs of nute burn. I backed off on nutes and the plant exploded.
My only point here is read everything, try things for yourself and make up your own mind. People think they all know best and try to make themselves feel important by dishing up "expert advice" and bagging on people for supplying real world experience. I overnute on a daily basis and have so for years. Just because you dont get it, dont bag on it until you try it yourself and have real results to share!
I will dig up the pics from my last grow and post a journal. I consistently yield result people bet me money are lies. then I show them the pics and collect. a pound per plant indoors is difficult, but possible. I rarely get less than 6 oz from one plant indoors.
Now feel free to apologize. kiss-ass