I'm not a export , but I have had to learn a lot this year ,a lot of loss ,a lot of grief ! but I have found out that humidity seems to have a HUGE part of hatching turkey eggs .I tried at about thrirty five percent for the first part and then up'd it for the hatch period and found that the chicks were weak from trying to get through the shell ! ( lost everyone of them )! Then I up'd the humidity to fifty five percent for the first part and then up to and past seventy five percent for the hatch and they were way stronger , busted through with out any effort ? But that's justr how it worked for me ? might not work for someone else