Hello

Coturnix quail males should have at least 3 females, normal is about 5 hens per roo. This is because during mating season, the male will injure the hen(s) and/damage their feathers by overmating them, so the more hens he has the less chance of damage happening.
To introduce quail, house them side by side with a safe partition between them for 1-2 weeks. They *should* get used to each other within this time but not always and even if they appear to be getting along, they still need to be closely monitored for weeks after because this can get bad and bloody very quickly.
Make sure to have as big of a cage as possible with lots of things to break their lines of sight/hiding places in case there is bullying. I like to wrap up a few handfuls of hay and just bend them to stand as hay trees in the corners and the quail love them, they feel very cozy behind them and the top of the hay folds over to create a cool "hay cavern" for them
As for males, adult males will not tolerate each other and even being in different cages near each other can make them upset and ferocious in their mating because they perceive competition.
So first step is figuring out who the males are and put the remaining females you want to integrate with your pair in a cage beside the pair's cage. Or, if there is enough room, you can partition the quail pair cage and have the pair on one side and the new quail on the other. Good luck!!
