[ness]

Hi
My two mummy hens have successfully reared two chicks (one each although they are not mutually exclusive   ).  I am looking to find homes for the chicks as they are 8 weeks old.  They are still on chick crumb at the moment as I have a huge bag of it  :roll: and am hoping to rehome the chicks before having to go onto growers.
The problem is that one of the mums is making laying noises and checking out the nest box hopefully looking to lay   - but I can't give her layers until the chicks have gone.  How do I ensure she has enough calcium?
Any help gratefully received.
Ness