Add warm water to the pan as needed. To boost humidity, increase the size of the pan or add a wet sponge. You can also adjust the humidity by adding or cutting back on airflow. If you don t have a wet bulb thermometer, you can check humidity by noting the size of the air cell in each egg. The air cell grows during incubation at a certain rate based on temperature and humidity.
Ventilation is adjusted by opening or closing the sides or top of the incubator.
Normal air exchange is needed during embryo development. The embryo needs oxygen and produces carbon dioxide. You ll need more airflow as the chicks begin to hatch. However, you should maintain correct relative humidity until most of the chicks are out of their shells. Do not open the incubator unless necessary during the last three days of incubation.