Aqua One Activated Carbon Filter Media ChemiCarb 600g Aqua One ChemiCarb can be used in a large variety of filters, contains no phosphates and is suitable for freshwater use. ChemiCarb has a large surface area which absorbs fine particles which are held in suspension in your aquarium water. Water is passed through the carbon which traps the small particles in its pores. Includes free fine mesh filter bag allowing you to use the carbon easily in any filter of your choice. It is recommended to remove and fully replace ChemiCarb every 6-8 weeks to avoid releasing the waste back into your aquarium. Creates crystal clear water Removes toxins from your aquarium water Removes dissolved organics, medication after use, leached tannins For freshwater use only Includes netting bag (15 x 20cm).