So you’re just using micro and grow? Or do you mean micro and bloom? How much of each are you adding per gallon and how often? When you water are you letting 10-15% run out the bottom. Looks like a lot of tip burn for only 600 ppm. Did the get overly dry at some point? Looking again at the last pic your further along than I thought. Could simply be natural maturity. At this point I be wary of knee jerk reactions.