What food should I feed them to make there eggs tougher?

[claud]

How old are the hens? Mine often go through the "rubber egg" thing when they first start laying for the season - calcium or no calcium.

 

[bigdog]

They're 9 months and have been laying for about 1. My other hens of the same age lay real hard eggs.

 

[claud]

I have 12 hens all the same age and some lay "rubber" eggs at the beginning of their laying cycle and others don't. Usually it only happens every few days though. Yours may be because they are so young. The problem may resolve itself.
I also have 2, 9 year old hens that sometimes lay weird or rubber eggs - but mostly their eggs are ok - I figure it is because they are so old.

I often find these rubber eggs under the roost - I figure their reproductive cycles aren't regulating themselves quite right yet.