So my first two hatches were a disaster and only one chick hatched from each lot set. So now that I have had some advise on why they may not have hatched (temp too low / humidity too high / not enough oxygen) I have modified the incubator and I can't get the humidity over 23% It is a home made incubator - styrofoam box type. Temp is now set at 37.4 - 37.9, it has a number of oxygen holes, shallow dish with 2 sponges full of water and has a fan to circulate the air. Any other changes and do I need to bump up the humidity before i set any eggs? I am worried I wont get many hatch again...so want to make it right this time.