Our chickens are now three months old and I was wondering how long do we need to feed them the medicated chick food? We give them treats almost every day - their favorite is grapes (we love to watch them chase each other). Also, do you lock your chickens in their house at night? They go in the coop themselves but we lost one chick - came out one morning and something had eaten it's head (ugh!). Weren't sure if we needed to close up the coop when its really cold too - like in the 20s. We also haven't made boxes yet for laying since they are still young. Any help would be appreciated BYC folks!! Thanks.