Mobile Bay Reef Keepers

I believe running carbon is really making a difference in my tank. In fact if I don't change it fast enough, I see negative results in the sps. I'm sure there's lots of chemical warefare going on..<shrug>
Anyways.. since I am going to be stuck running carbon, I'd like to find a good deal on it.. Anyone seen an online vendor, or local that has good prices on largish amounts of it?

Thanks,
Brandon

Well so far I just order Black Magic from Petwarehouse in the large gallon size containers.