Feed suggestions for older hens

[NatJ]

Lack of calcium can cause the soft-shelled eggs, but not the no-yolk fairy eggs.

In older hens, soft shelled eggs can mean the shell gland is misfunctioning due to hormone changes or infection. You can feed them all the calcium you want but shell quality will not improve. Some chickens will develop further illnesses and succumb to the infection and others will survive and stop laying eggs. You can feed them All Flock feed and offer oyster shells. They may or may not eat it.

^As you can see, soft shelled eggs can have several causes. How much calcium the hen eats is only one of the possible causes. I can't say which cause is affecting your hen.