Nute Burn after 2 ever NPK doses! Day 37 Flowering.

You gave them a feed from a fertilizer that had the NPK ratios of 43-3-2??? that's a lot of nitrogen. To much nitrogen and if you did not monitor the strength of the feeding solution then its even more damaging as I don't see a EC number on your diary just a PH reading. Any time when using liquid nutrients "especially new ones" you definitely want to monitor the EC/PPM of the solution to avoid over feeding and lockout. I think your feeding gudiline of 5ml/l was to strong and this is why you are seeing the burning. Your plants most likely will need a flush to get that out of the medium and you will need to invest into a more wel rounded feed that is close to 1-2-2 in terms of ratios. or even something like 2-3-3/2-4-5. I use a Gaia green bloom and veg dry amendment fertilizer together and there ratios are 4-4-4 veg and 2-8-4 bloom when mix at 50/50 it becomes 3-6-4, potassium is a little low but it works. I'm sure the other amendments I use make up for it. So in short this is what I see, you over feed with N, its going into toxicity and burning the leaves, you need to flush it out and feed a better more well rounded fertilizer. Good Luck!