Pack of two odour and nutrient Removing replacement cartridges for the Aquarium Systems Cobra Internal Filter Range as well as other internal / external filters. Newaqua Diamante is a hyperactive carbon of mineral origin (peat) extruded in small cylinders. Given its macroporous structure and the large surface area, Newaqua Diamante has considerable physical and chemical absorption capacity, which means that it attracts and retains numerous harmful substances both outside and inside.Newaqua Diamante is recommended for freshwater and saltwater alike. It does not alter the pH value. It does not release phosphates. Newaqua Diamante does not produce any dust. In mechanical terms, it is very sturdy and has a low ash content. It eliminates algicides and proteins dissolved in the water. In saltwater aquariums, Newaqua Diamante absorbs the toxins and urticant substances in corals.