Hi, I have a heat pad which is 15 inches long by 12inches wide. Will this surffice for in the coop for my 3? My birds aren't fond of anything other than the starter feed apart from a garden earth worm my daughter threw in for them and they all went nuts including the little one fighting over it. but i've tried boiled mashed up egg, green veg and brocoli and they all took one investegative peck and ignored it and happily dug wood shavings over it all until i eventually took it away. My pink poo bird is the small one, sh'es supposed to be the same age at 3 wks as the other two but proper tiny in comparison. She also has the occasional sneeze and is sleepier than the other two. I'm worried about her and don't really know what to do. The breeder keeps saying she's fine but i don't feel she's coping as well as the other two. Should i be worried? I think my two bigger birds would do ok in the coop with a heat source, but I'd be so upset if I put the little one out and she died of cold or something. The temp for the next week here in the north west of england is due to be 17/20 max but a bit of rain too. Thanks for any help