i am in anchorage, alaska and broodered my bunch with one 125 watt brooder lamp. they will be fine. you need to set the light in one place and try togeta consistant temp. then moniter your chicks. if they are huddiling under light then they are cold. if they are well outsde of 12 inch circle under lamp then they are too warm. if they are wandering about then its probably about right. try using an outdoor digital thermometer with outdoor lead on flooor of brooder about 8 inches outside of lght source, as it will give you the best reading of what chicks temp is. they will occasionally lay on thermometer lead and then you will get the chicks actuall body temp.