Juwel BioPlus M Coarse Sponge for Bioflow M System (3.0). The Juwel BioPlus Coarse Sponge is designed to remove large to medium particles, and its design allows bacteria to thrive and multiply thanks to its large surface area. It is recommended to change the BioPlus Coarse Sponge every 3 months to maintain the filter's highest possible efficiency. Suitable for JUWEL models Rio 125, Rio 180, Rio 240, Vision 180, Trigon 190, Lido 120, and Lido 200.