50/50 mixture of Matrix Carbon and Phosguard. Removes phosphates, silicates, metals, and organic substances. More effective than the two products individually. Seagel is a 50/50 blend of Matrix Carbon and Phosguard, specifically optimized for aquariums where the removal of organic substances and acids is necessary without introducing phosphates. Matrix Carbon is the most effective activated carbon on the market for removing organic and colored impurities. Phosguard is a strong remover of phosphates, silicates, toxic metals, and acids. Both are in pellet form, allowing for optimized water flow. The two components enhance each other and are ideal for use in saltwater.