I have glanced over a few other threads concerning lighting schemes in coops, but have noticed no discussions about different "shades" of CFL bulbs. I would like to discuss my experiment with different "shades" of CFL bulbs and the effects on my birds. First of all, i have 5 breeds of chickens and coturnix quail, the lighting schemes and effects below are the same for all. My lighting scheme turns on at 4;30 am and goes off at 7:30 am.around October after most of the moulting is over. I light my whole run(s), not just in the coop, with 23w CFL bulbs. The lights shine through the windows/doors and the birds become active. If you look on the box of CFL bulbs, you may see a number followed by a *k. This is what i call "shade" in layman terms. The *k value starts off low as orange shade and works its way to white then blue being the highest *k numbers. In the past i used 100watt edison bulbs with some success, but using 5 100w edison bulbs (not counting my brooders) adds to the electric bill quickly. So last winter i decided to switch to CFL bulbs. Last winter i used 2700*k bulbs which is more towards the orange side of the light spectrum. My birds layed decently, but were not very active until natural daylight took over. This winter, i am using 5000*k bulbs, which is a balance of blue and white in the light spectrum. My birds are laying more, the roos crow more, and the birds are noticeably more active than the 2700*k bulbs or the old edison type. They seem happier, so this is the "shade" i will continue to use from now on. I am no expert at writing lighting or electricity, so excuse me if everything is not correct.. I have tried to make this easy as possible to understand without all the "scientific jargon" i could have researched.