Seedling problems!

ive got about 10 autos growing under a 600w using soil with perlite and vermiculite (sp?) most of them have sprouted nicely but there are one or two that havent or have hardly broken out of the soil. On closer inspection they have first small leaves but they aswell as the stem look skinny and flimsey almost like i have put them in the microwave! Cant provide pics yet but from that 'description' can anyone tell me what im doing wrong.

Im watering with a spray nozzle every couple of days until the first inch or so is moist. The top of the soil is drying out quite quickly from the heat of the light.

Any suggestions??

Couple more days and ventilation, no need to have the light too close on the seedlings either. Keep the top of the soil moist by spraying a couple times every few hours.

thanks a lot my light is probably just over a meter from the tips i have sprayed a couple of the healthy ones but was hesitant to do the same to the sick ones through fear of overwatering. Here is a pic of one sorry about the poor quality