Oase BioMaster 30ppi Pre Filter Foam

Features: Pre filter foam for Oase BioMaster Various pore sizes available Various set sizes available Doesn't rot under water   The Pre-filter Foam Set 30 ppi for the BioMaster 250, 350, 600 and 850 includes 4 coarse replacement filter foams Customize your choice of filter foams to meet the needs of your aquarium Timing to replace the pre-filter foam set varies upon aquarium size and the number of fish and plants