To be honest,I definitely agree about the usefulness of ".edu's", i guess its really just another anecdotal data point in the grand scheme.
thanks for the candor, I don't really know squat about saltwater yet but I would lean towards its a marketing ploy for freshwater. Then again, maybe if you way overstock/overfeed a tank, even freshwater, the carbon might be needed.
I dont know if chemi pure is the same as regular carbon, but id recommend it to someone any day. I would buy it for someone if they needed it. It is one of the wonderful and few inexpensive things we can enjoy in this hobby.