Just something I noticed

[LilyD]

Me too I would love to be able to make all (or at least most) of my hatchers girls hehe

 

[Ceinwyn]

It won't work unless you want more roosters than hens.
The sex is determined before the egg is laid.
Studies have shown however that male embryos can take a higher temperature before being killed.
Therefore you can incubate at a higher temperature and end up with more males because you kill the female embryos.
It's not like reptiles were sex is determined by temperature.