Remove dissolved organic compounds that pollute and discolor aquarium water. HydroCarbon2 is a high-capacity granular activated carbon designed for water purification. Diverse pore size and large pore volume provide rapid adsorption of aquarium pollutants, especially dissolved organic compounds. HydroCarbon2 resists clogging, has very low ash content, a neutral pH and positively does not leach phosphates. Versatile and long-lasting HydroCarbon2 can be use in high-flow and low-flow applications and after months of use, it also becomes a very active biological filtration community full of beneficial bacteria and microorganisms. One liter treats approximately 400 gallons. For marine and freshwater aquariums. Use with a filter media bag.