Carbolit comprises of highly efficient activated carbon pellets. carbolit quickly clears up aquarium water and removes colouring substances, turbidity and medication residues. Yellowing substances such as phenols and tannins that can accumulate in the water are also removed. carbolit may also be used as a long-term filter material. After a short period, bacteria settle on the pellets making the carbon work as a biological filter - aerobically and anaerobically. carbolit is pH neutral and can be used in fresh and salt water aquaria. 500 g for 125 gallons. 1.5 mm pellet size.