JUWEL Cirax consists of very porous ceramic-based pellets, which create the perfect environment for the filter bacteria due to their extremely large surface area. Cirax helps ensure excellent water quality. A special filter basket, which is tailored to the size of your JUWEL filter, allows for easy handling, while the optimized load capacity provides a long service life of up to one year. >excellent water quality due to effective biological purification >extremely large area due to porous filter material >suitable for use in freshwater and saltwater aquariums >LxWxH: 14x14x5cm