JUWEL Cirax are highly porous ceramic- based pellets which, due to their extremely large surface area, create the perfect environment fulfilled the bacteria. In your JUWEL filter, Cirax helps to ensure excellent water quality. Using a special basket, tailored to the size of your JUWEL filter, makes it easy to use, whilst the optimised filling quantity means a long service life of up to a year. Characteristics of JUWEL Cirax • Excellent water quality due to effective biological cleaning • Extremely large surface area due to highly porous filter material • Suitable for use in freshwater and saltwater aquariums