How much to give

I have bought the cod liver oil, poultry spice and limestone flour (in equine quantities) but how much of each do I give?

I only have two hens (one with soft shell problems). Do I need to give tiny quantities daily or could the suppliment be given a couple of times a week and still be effective? I've been guessing for the past fwe days.

Had some results though - last egg from the soft shell layer was hard if a bit grainy and in the nest box.  Perhaps its the suppliments or perhaps my girlie is maturing.

Thanks