Plants all dying

No answer to your question. Just wanted to say thats ashamed and wish u the best man.. sucks..

Did you check PH with every watering? I'd say it's either bad PH or some root problems

Ok seen this before and you can save this IF its the same thing. See my Stardawg grow. Something organic may well be amiss in your soil. Flush with 2% Two percent FOOD GRADE H2O2 to 25% run off. (If you put in a gallon you want 1 quart of runoff) Do not use brown bottle drug store stuff. That is normally sold in the 25-30% range so you are looking at 10-12 parts water to one part H2O2 approximately which is fine. It will not hurt plant or buds at 2-3% strength. Feel free to ask any question you like When it drys enough continue feeding at half dose see how things work out.

those tips do look burned so that is a sign of nutrient burn, but there's something else going on that's leading me to think there is a problem with the roots. Hopefully, I answered your question and remember Happy Growing and Free your mind one puff at a time.