Our 2 week old chicks used our Premier heat plate for the first week or so (primarily to sleep in and then they were up and about during the day, occasionally going under the heat plate for a bit of extra warmth), but in the past few days they barely use it. They have been sleeping all together at night (but not under the heat plate) and are pretty active and chipper during the day, using the plate very sporadically. The temperature in the coop at night ranges from high 50s to mid 60s (this is about the same as when we first got them)- this is about the same temperature as week one. I've adjusted the height a bit to accommodate their growth and have one side that is lower than the other. The chicks are energetic, growing and seem healthy. But I am worried that they are not using the heat plate? Should I be? And if so, how to get them back under the plate at night? Maybe I need to make the height even higher (is there a recommended height for 2 week old chicks?