Has anyone seen the MarinePure biomedia? It is expensive but looks like a great way to add extra space for bacteria in a reef tank, With all the surface area it seems like it would be alot better then rock rubble. It would take up alot less space, easy to remove and clean in old tank water aswell. I'm still not a big fan of traditional bioball setups, but using this stuff after a filter sock or some other kind of filter so it can't trap any detritus and I would think it would be a good setup. They have "bioballs" and plates.
http://www.bulkreefsupply.com/store/...?q=marine+pure