OASE BioMaster Pre-filter Foam Set Blue, 1ea/6 pk

The Pre-filter Foam Set 45 ppi for the BioMaster 250, 350, or 600 includes six fine replacement filter foams. The combination of coarse and fine filter foams allows you to customize to meet the filtration needs of your aquarium. Timing to replace the pre-filter foam set varies upon aquarium size, number of fish and plants, and declines in filter performance.