My chicks, 2 RIR, and 4 EE, are about 3 weeks old. I moved them to their coop today. The thermostat is currently reading 88 degrees at 10:30 p.m.. The overnight low is close to 70. Should I hook up a heat lamp just in case, or do you think they'll be okay for the night? I'm afraid that they'll get too warm with the light on, but on the other hand, I don't want them to get chilly either. My husband built them a green roof coop. They are shut into the hen house portion, which is pretty draft free. I'd rather not set an alarm to check on them at 3:00 a.m. - do you think I need to worry? Thoughts or reassurance greatly appreciated - these are my first chicks.