This system includes: Fleck 2510SXT AIO Digital Control valve 12x52 Fiberglass Mineral Tank 3/4"or 1" stainless steel by-pass 2 Cu. ft of Multi-Media (Birm, Calcite, Filter AG, Carbon) 1 Sleeve of gravel 1.05" Riser Tube Funnel and Cap Aqua Science multiblend consists of a mix of Birm, Calcite, Filter AG, and Carbon. It's specifically designed to reduce Iron and Hydrogen Sulfide while increasing pH.