Just a quick pic of my new layer pullets with my seedling mat brooder cave. Just got them in the mail this morning. The red lighting is just Christmas lights way up high on the frame of the converted plant growing tent the brooder is set into. I feel they help cut down on pecking, but can't prove it. No heating lamps or light bulbs for me!
The seedling mat is waterproof and thermostatically controlled. I also use other remote digital thermometers and a regular old school thermometer to keep track of the temps. This is a very large mat, about 4.5 ft x 3 ft. It easily keeps temps about 15-25 degrees F above ambient temps (can push it higher), which works for MY situation. It's on a wire base made from shelving I had around, half is on a sheet pan/cookie tray. I make different heights along the length so the chicks can pick their comfortable temps.