Hello,i have 2-9 1/2 week old babies.One is a sizzle and the other is a batam cochin mix.I have them in a grow out coop thats 3x5x6 and has 2 inches of insulation in the walls and floor.I have a 90 watt heat bulb that i still want to put on at night,but my DH says they dont need it.Temps will be 31 tonight and will be only 25 tomorrow night.What do you all think??