Quote: The bottom line is: I don't need to know the exact humidity, as the air cell will tell me if it is correct !
Use your hydrometer, it will help you with the general readings. In my LG: RH was running 35-40 % until front passed thru; dropped to 25%. Do you have a diagram taped where you can use it during candling?
A youngster bought eggs from me twice this spring to try out her homemade fishtank incubator. First try 4/18 hatched. THen she revamped the incubator design. AND increased the air flow AND used a diagram. 8/16 hatched. I hatch 90% of those eggs, so I KNOW the humidity is the problem. Eggs are not loosing enough moisture. Maybe some others can comment on how much moisture to loose for a marans, generally I read 11-13% drop in weight of the eggs.