For me working on a very small scale - 2 beds, total space 3 x 22 feet, I have noticed that the semps seem to like the dust from the chick grit, so I don't even rinse it. Whenever I renew the top dressing, they seem to perk up within a day or so. I find this very interesting, I'm sure there are minerals in this stuff that they like
Kate sorry - what a mess! I can't imagine that this isn't available there given like you said, being near mountains. Also I can't imagine there aren't chicken farms around?? Its odd
Good luck with it all though!