Ok, 6 chicks are 4 weeks 4 days, 2 chicks are 3 weeks 4 days old. gotta get them out of my shop. Night temp has been in the mid 50's to low 60's at night, highs during the day 90. Do you think they will be ok to leave in the "outside" brooder , it has three solid sides and wire front (as compared to the cardboard box in shop) until old enough to put in brooder. I can ,if needed, mount a heat lamp on the screen front. The cardboard box is getting too small for them.