What I recommend

A formulated feed should make up the bulk of what a laying hen eats. Scratch mixes and kitchen scraps are treats, and a flock living mostly on them ends up short on protein and calcium.

Useful as a top up for birds in moult or coming back into lay, when appetite is down but demand is up.

A supplement alongside a complete feed, not a replacement for one. Fed on its own it leaves a laying hen well short of the protein and calcium she needs.

Offer it free choice in its own container rather than mixing it through the feed. Birds take what they need, and mixing it in means the ones who need it least eat the most.

For a hen laying thin shelled eggs on a diet that is otherwise sound. If more than one bird is affected, or the change came on suddenly, look for a cause before adding a supplement.

A liquid calcium, which suits a bird who will not take grit or who needs a short, measured course rather than free choice access.

Worth having on hand for a flock under stress, after a move or a change of feed. It supports a gut that is coping. It does not treat a bird that is already unwell, and it is not a substitute for worming.