If an incubator has too little moisture, the amount can be increased by increasing the area of water available for evaporation. A bigger pan can be used, or sponges can be placed in the water. The air flow through the incubator might also be decreased. Some air exchange between the inside and outside of the incubator should happen continuously to replace oxygen used by the developing embryos. When that need is met, air exchange can be managed according to heat and humidity requirements.
More air flow tends to lower incubator temperature and humidity.
In commercial incubation, eggs are placed in flats, and the flats are automatically tilted back and forth every hour. The purpose of turning is to prevent the developing embryo from sticking to the shell. For eggs in small incubators that do not have an automatic turner, it is recommended that they be turned at least three times a day. To assist this procedure, place a mark on each egg with a pencil. Alternate the position of the mark when eggs are turned.