I have a flock of 8, currently. 6 confirmed hens, 1 rooster for sure and a second I'm fairly certain about but in denial. Town rules state one roo for my square footage. My chicks are all between 5-6weeks of age. At what age do most rooster reach maturity and how long after that before I know which rooster will be my "keeper" - or the one which is the least aggressive to us and to the girls?