help! pics. browning leaves, yellowing leaves

ok so these poor ladies have had a rough 2 months... yes they are 2 months old and this sad...

they are about 2 months old, are in miracle grow all purpose soil. they are watered when they need it, no more, no less...

they are under a 400 w MH on a 24/0 schedule

they have had browning leaves and yellowing leaves.. they just fall off but new shit still grows. what am i doing wrong.

today i gave them a little bit of nutes, this is the first time ive done this as i didnt know if it was nute burn or lack of nutes killing them. i also have started giving them distilled water from today untill harvest

any help would be great. i couldnt tell you the pH but the temp is in the 60-75 range

here is what they look like

your ph is way out imo,they turn it to mutants

You definitely want to check out that pH even if you've only been putting in distilled water. I was really surprised to see that my pH had shot up to 7 in a matter of days, without even adding nutrients. The sooner you nip the pH in the bud, the better!