Cornish rock is another name for.the.cornish cross. They cross a cornish with a white rock chicken. 2 birds out of 25 is not bad. You want to keep your losses below ten percent. As far as the field shelters go, you can fit 80 to 100 cornish X's in a 10 x 12 pen as long as it.is moved daily...
Forget the candler, don't trust the thermostat or the hygrometer. Buy a large display lcd dual thermometer and hygrometer. The adjustment dial is very sensitive. Don't get picky with it and be patient. Love mine.