weak egg shells

[Henhorse123]

Hi
I recently got 4 chickens and 2 of them(older bluebells) are laying well and one of the Sussex is doing her best but the egg shell are weak and seem to just break when I pick them up or are just empty core. Is this just an age thing or should I try adding vitamins etc. to water and food? She is only young though(around 19 or 20 weeks) and the other Sussex isn't laying yet.

 

[Purechick]

Try giving them oyster shell. It will help give the eggs a stronger shell.