Which is the best carbon and phosphate remover?

[tmz]

I use purigen, unlike the resinns in chemipure, it is designed to attract organics and may attract some that gac won't and vise versa. If I had to pick one it would be gac.
Lots of folks are having problems regenerating purigen:

http://www.reefcentral.com/forums/showthread.php?t=2153756&highlight=purigen

The best I can say is be sure the bleach is gone and don't dry it out before reuse.