burned leaves

hi guys what is wrong with this plant?
medium- peat moss 70% perlite 30% (ph 4.0~5.0)
nutrient- foxfarm
watering-everyday(nutrient mix with tap water and i didn't check p.h after mixing.)
the leaves are getting brown spots and keep dying.
i don't know why please help thanks

Can you post a picture?

Guessing a low pH/calcium issue. Straight peat is acidic, adding fertilizer will drop pH further. Your soil and ferts are lacking calcium, and the low pH would make it unavailable if it were in the soil.

Yup your ph is way low due to peat moss being extremely acidic you have to amend with dolomite.

We have no idea ,what week you are at,Are you in Flowering or veg,if you are in veg and its the odd leaf don't Panic the odd leaf will often die,Or if you are in flowering think of it has been fall in your room,leaves die off, in that season,in nature ,But if a lot are turning up dead,or dieing, then you have a problem,If you are growing under hps whats your temps,More info would be better,This is like going to a doctors and saying im ill with out saying where it hurts.Or telling him any info why you may be ill .