. . .The other thought might be to tie the cat traxs to the mooring, they should float.
I like that! As long as they don't float away! <img src="http://www.catsailor.com/forums/images/graemlins/shocked.gif" alt="" />
For a regular mooring, I think chain is best. It won't damage other boats and it will silt in, giving great holding power. Just put a "bobber" on it when not using it so you can find it.