Jewel BioPlus XL Jumbo fine sponge for Bioflow XL (8.0). The Jewel fine sponge filter media is designed to remove small to medium-sized particles, and its design allows bacteria to thrive and multiply thanks to its large surface area. It is recommended to change the BioPlus fine sponge every 3 to 9 months to maintain filter efficiency. Suitable for JUWEL Rio 400/450, Vision 450, and Trigon 350.