5yo RIR feeble eggs both the shell and the whites

[Gecko Chick]

Silent Bob has been laying weak (not wrinkled) shells--some broken, some really soft--and both of our two chooks have egg whites, that, when you break them into the fry-pan, the whites are sort of opaque when they cook and don't look appetizing. Their yolks look fine.

They have full access to oyster shell, organic layer pellet and plenty of water and they're both free range on our acre for most of the day. We're in Hawaii and have lots of rain and we're just going into a higher humidity for summer, but this has been going on for months.

I read about Infectious Bronchitis but don't see any symptoms aside from the eggs. I just went out to look at Bob again to make sure she's not swollen around the face and I don't believe she is.

We're looking to add 2 more to our flock but want to first make sure we're stable.