The things that I've heard are that Carbon is not selective on what it filters out, that it will become a nitrate trap if not changed "frequently enough" and that some brands leach PO4
back into the water as a wonderful little surprise for you!
That being said I guess I should go move that carbon out of my sump. I think it's been there for a week now...
Join the NJ Reef Club
Today! Saving the world's reefs one living room at a time!
Atlantic City, NJ September 25-27, 2009