WAY too much epsom salt for any life stage is your biggest problem.
Young plants need very weak, if any, fertilizer. In MG soil there is already too much ferts for young seedlings, so they were starting off 'hot', then the addition of the liquid nute and epsom salt put them over the edge.
Combine that with being very close to a big lamp (too close unless it is air cooled correctly) and you are seeing the fert burn magnified.

Flush just using plain water at pH 6.7, raise the light (BTW, HPS is for flowering primarily, and you can get great results with CFLs in veg and they run cooler), go to a steady feeding of your liquid fert starting at 1/4 the recommended dosage and working up slowly.
stinkyattic Reviewed by stinkyattic on . Poor plants in bad shape, and I dont know whats wrong. OK I am "calling all cars" - I need some serious help. I have no clue what wrong with this crop. :( See pics below. I am raising them identically to my last crop which is flowering but looks pretty good. These look so sad. wtf4: I checked PH and it looks alittle high, on or above 7.0 so last night I added a sqeeze of lemon juice and 1 tsp of epson salt to help the PH and add some MG. They are in an airconditioned closet in my garage, HPS lighting 400 watt, and ventaliation fans. Rating: 5