LiquaGen - Replacement Water Filter Kit for 6 & 7 Stage Universal RO/DI Systems (Sediment, UDF/GAC, Carbon, 3 pounds DI Resin) This is an excellent replacement set for the 6 & 7 Stage Aquarium Reef Reverse Osmosis Water Filter System. The replacement set includes: 1) One 5 Micron Sediment Filter. 2) One GAC filter. 3) One 5 Micron Carbon Filter 4) One 3 Pounds RO/DI color changing Resin Deionization. DI Comes in air-sealed multi layered packaging to ensure a shelf life of 1 year PHYSICAL PROPERTIES: Functional Structure Cation (Hydrogen form) RSO3-H+ Anion (Hydroxyl Form) R4N+OH- (Strong Base) Physical Form Tough, Spherical Beads Ionic Form H/OH Screen Size Distribution 90 percent -16 +45 (U.S. St.) Moisture Content (as shipped): 65 percent max. Maximum Operating Temperature Non-regenerable 80oC* (175oF) Regenerable 50oC (140oF) Operating Flow Rate 2 to 10 gpm/cu.ft. (typical) pH Range 0 - 14.