Dark devil dying?

bro it is not dying yet but things may get worse if you don't transfer them to new pots. They are being burned at the moment.There must be some serious nutrient buildup in those small pots.Either flush hard or transplant.I would do the second.Just give the roots more free space to discover.Those pots will do the same thing again in a week even if you get over the nutrient burn problem.If you want to keep them in those pots still, I would recommend you a water+water+feed cycle until problem disappears but transplanting is a better idea if you would ask my opinion.Fat Banana doesn't seem to care about the buildup that much but others are obviously very sensitive to nutrients.