Minor Heat Stress????

I'm growing nirvana white widow in coco with gh flora trio + calmag. They are a little over 3 weeks old and look healthy. I just went to 12/12 3 nights ago. The plants are extremely perky and m all the branches hang a lot higher after dark period. During 12 hours of light they tend to sag about a inch but then perk back up through dark period. I'm using a 250 hps about 12 inches from plants. I wonder if this due to minor heat or light stress or not sure what the deal is. They are in fabric pots so shouldn't be root bound. I'm not too worried as long as they look healthy but this is my first grow so I'm just curious.

Do you have pictures

a 250w hps is more heat then light

compare the above consider a well vented 400w hps

good luck

They are in dark right now so no, all my side branches sag during light and perk back up during dark time. My leaves don't get droopy like over watering. The whole branch sags. Was just wondering if others had experienced this

Yea, I wish I would have got a bigger light but didn't realize when I was buying it. I can get it a little closer than 12 inches. I just got a new fan to blow directly on the bulb so maybe 8 or 9 now, I'm not sure.

I have a couple CFL's for side lighting in both red and blue spectrum so I'm sure that helps. My 250 watt came from htg and is suppose to have 33k lumen as oppose to the standard 27k for a 250. Weather this is true or not I don't know

They stretch for the light at night.....in their little minds they say "where did the light go, I better stretch so i can find it"....in a few days when they realize everything is normal they will go back into a regular routine again