How old does a hen and rooster have to be to produce fertile eggs? I believe that I have a Java rooster and a red oeg hen. They were gotten from a swat meet last Aug. (2009) and she started laying in feb. She has laid 12 eggs so far. I left the last 3 in the nest but the first 9 were put in a homemade incy and after candling they all are unfurtiled. I keep the heat between 99 and 104 degress F. Is this to hot or what? As you can tell I'm new at this and I'm doing for the grandkids. Any info will be used to the fullest.