Plant was doing great then it looks like this WTF?
Did I over feed?
You have to show entire plant, nutrient bottles, description of what stage your in, inside reservoir tank, genetics/name of plant, and close up of the problem to get an accurate answer!
Almost looks like Calcium deficiency. Is your Cal-Mag dispensing?
I ran out of bottles and tried to mix my own nutrition mix and I used some old bottles I had they were new but years old I think they were bad plant totally died roots got red and foamy I took it out and started over luckily I cut clones before I flipped to 12 12 so I had one ready to replace just ordered some new bottles and try again