I have a flock of 60. We are in Fairbanks AK, it gets very cold -40 here, so my chickens actually have their hen house in the basement. Plenty of space, good ventilation, lots of roosts, and when the timer turns out the lights, it’s is coal black in their pen. I have seen a lot of speculation on this thread and others on here, regarding “nocturnal” chickens. I’m here to tell ya, half of mine are. They are all pure bred, (BLRW, LO, SS, fayoumis, SF and Cochins) and young. Hatched and raised by me. No red lights, no light at all. But they do their thing all night. I can hear them, they eat, drink, peck and hop on and off the roosts and into nest boxes. I have had chickens all my life, and I’ve never had chickens that did more than rustle after dark.