The overnight lows are about 45F - I moved the brooder outdoors. It has 4 walls and a tarp loosely over wire on the top (there is ventilation). I have a Binsea EcoGlow in there - there are 3 x 5 week old chicks and 2 x 3 week old chicks. Think they will be ok or should I move them in? (I'd really rather not but dont want them to freeze).