How to calculate kitty litter for coolidor

in Cigar 101
I am expanding my cigar collection and am getting everything together but havent found anything on how much kitty litter to use. If 1/2 of beads will do 2.5 cubic feet is that the same for kitty litter?
Comments
some say you need a little more KL than beads, but I think the capacity is roughly the same. Of course the more you have, the more stable.