I have 8 that will be 4 weeks old on Tuesday. They have been outside from day 1. I close them up at night with the light and let them out in the run in the morning. The lows at night are mid 70s currently and the highs up to 100 already. We did have a cold spell earlier this week lows were in the 60s and high mid 80s When can I turn the light off? Lately I have been more concerned about them getting to hot than cold.