Big Blue vessels are used with DI resin by marine fish keepers and window cleaners for lowering water TDS after a Reverse Osmosis unit. They are now being used by fish keepers and know as big blues. These are filled with differing carbons to remove chlorine and chloramine from the tap water. Used in conjunction with a 10” x 2.5” pre- filter housing to remove the sediment from your water supply. The vessels can be bought as just a resin vessel or the complete set up with a sediment filter housing. The complete pack will include Gac, Bone char, Catalytic carbon.