Twisted, wilting, leaves???

Hi I am new to the site and to growing. Here is my set-up:3' 3 1/2" L x 3' 3 1/2" W x 6' 7" H, Can-fan & Filter, 400w HPS light positioned 2 feet above plants. Plants are starting the 3rd week of vegetative growth. I have planted them in 20 oz cups to start em. No nutes yet, and the plants were looking great, growing fast, really bushy looking then all of a sudden they have started to die. Like 2 days ago the bottom half of the plants leaves twisted, and I mean twisted like 180 degrees and some are cupped upward(the whole leaf). Yet the new growth on the top looks great. Now the bottom half is drying up badly, really crispy feeling and the plant looks skinny and everything is just hanging down. Anyone have any insight??? Thanks in advance.

Anybody??

Pics Please, upward cupping can be caused by temperature problems. But without pics it could be a number of things.

I have had an "over watered" look with my plants from a pot not being large enough. Im not sure if that Is what you mean by everything "hanging down." You need to get a pot where the roots can expand freely. As soon as the roots start to wrap around the outside the plant will start to droop.

As far as the curling up goes, Im sure it is due to heat stress. I have experience with a 400 watt HPS, and heat is definitely a problem. I have gone so far as to keep the light at least 5 feet away while using a fan directly on the plant forcing heat away. If heat stress is a problem you will probably notice yellowing around the edges of the leaves and/or "burn" looking spots on the leaves.

I would say repot NOW and get that light away with more air circulation. Check your temps. The largest problem you might be having is with not enough root room. Just my opinion from what I have experienced though (i grow using 5 gal containers :thumbsup: )

Thanks guys, that would make sense because they are getting that over watered look. I will repot, today and next time I will have pics.