tell him to google it.... Calcium is acidic.... It will tear away at their crop liner...... this is really important
https://www.backyardchickens.com/t/106435/effects-of-feeding-layer-feed-before-the-right-time
another article
https://www.backyardchickens.com/t/106435/effects-of-feeding-layer-feed-before-the-right-time
another article