What is the best type of activated carbon to use in a filter? In my research I'm assuming it's the type made from coal. But I can't seem to find information on size, pellet or granular, etc. I think I remember reading 3 mill for size but forget where I read that. Also, can someone direct me to the best place to purchase and if it's ebay, is there a particular seller that is trusted more than others? Thanks for any info.......one more ? ...how much would one need to fill an 8x24 inch long with a 6 inch core filter?
