Curling Cotyledons

[slewis]

I noticed a day or so ago the cotyledons on a couple of Jalapeno plants are starting to curl under. From what I'm finding upon doing some digging is as follows:
 
1. It can be normal when they start to develop their first set of true leaves. No idea if this is accurate.
2. Over watering
3. Too much light
 
I've been watering through the bottom enough to make sure the top of the soil is damp, not wet. Previously I had a small LED light sitting about 3-4" to the top of the plants cycling 18 on 6 off, but have since moved everything over to a 4' - 4 Tube T5HO. This is sitting at about 12" - 15" to the top of the plants as of about 30 minutes ago. Soil temp is holding at about 80 degrees. Also, the tray is on top of a heating pad. Can I remove the pad or should I keep that in place?
 
Thoughts?
 

 
 

 

[podz]

I'd guess too much light.

 

[Pharthan]

I was curious as well so I started looking things up for it, too.
There wasn't a lot that was too definite from what I saw, but some people suggested it might be overwatering, if you aren't letting the soil dry before rewatering that might be it. Some said too much light, some said too little, and some said not to worry unless it starts happening to the first true set of leaves as well.

 

[slewis]

I cut the light early tonight, so I'll check it in the morning and see if they opened back up. If they do, I'll raise the T5 and see what happens.