AQUA ONE 2c Replacement Cartridge for Aquastyle 510\n--2 x Replacement Foam each\n--Wool and Carbon\n--Replace 6-8 weeks depending on biological load * NOTE* Due to the the nature of how the Carbon is manufactured, there may be some particles which will naturally fall from the cartridge into the packaging. It is advised that before use, the filter cartridges should be rinsed in water before using in tank.