I've posted a few times about what lietter to use in the litter pans.
You can use the same 'litters' under the mesh floor.  My first choice is
wood stove pellet fuel (available from wood stove stores).  Second coice
would be a retail cat litter called pine fresh.  It doesnot seem to have
the added aromatic oils like the shavings.  You could try the recycled
papar type or the corn cob litter as well.  I wouldn't try the pine or
cedar shavings at all.
 
bill and diane killian
zen and the art of ferrets
[Posted in FML issue 1260]