Can I?

24 hours of light is a bit detrimental. It shortens their lifespan. If you are breeding them, 16 hours of light is ideal, 12-13 hours if they are on "break"

 

Yup ,give them a night time. All my birds sleep with the natural cycles of day and night ,and all my birds do fine on it. Quail ,partridge ,softbills ,hardbills ,everything.

I've seen what happens if you dont let birds get enough sleep. They get really pissy ,and dont do as well.

ETA: The only birds I have who get light all the time are my chicks. And they always have a small house to hide in should they want to be in the dark.