I have a still air incubator with an automatic egg turner and have my humidity around 40-50%, but my question is, i add eggs everyday, not put 20 in at once, like 2 a day. So i cant really increase my humidity on day 18 because the other 30 eggs need it at 40 or so. What is a good humidity that would work for new eggs and eggs on days 20? thanks so much yall