Morning Deerling,
With a broody box 7 feet long I would block it off at about 4 feet at first. Once they figure out where the warm spot is you can increase the size available to them. he purpose for the second light is in case tone goes out, I can see where it could be helpfull if brooding a BIG batch of chicks to prevent crushing also. 25 chicks will be fine under one light, I've had 40 do fine under one. Have your cover ready, they learn how to jump guickly.
With a broody box 7 feet long I would block it off at about 4 feet at first. Once they figure out where the warm spot is you can increase the size available to them. he purpose for the second light is in case tone goes out, I can see where it could be helpfull if brooding a BIG batch of chicks to prevent crushing also. 25 chicks will be fine under one light, I've had 40 do fine under one. Have your cover ready, they learn how to jump guickly.