whats up with my plants??!!!???!??!?!?!

Ive been on here a bunch of times asking cant figure it out. plants are a month old some leaves look like shit. my temp is 70 humidity is 45- 55 %
fed every 5 hrs at 40% nut strength. damn for a first time grower I thought i was doing good. here are some pics. Pic 1 was light green for a week or so before it turned brown. If it is nute burn it has been going on for nearly 2 weeks. what should i do?if i have to start over can i clone em instead of starting over?

stop feeding so often... if you know its nute burn why are you still giving them nutes... lay off to see if they heal up

my ph is usually 5.7 - 6.0 it changes so often its hard to get it to stay at a certain ph