Marineland/Aquaria Bio Wheel Assembly Replacement for the NEW Penguin 100B, Penguin 150B, Penguin 200B and 350B.  Marineland/Aquaria Bio-Wheel should not be replaced unless damaged.   The water flow from your filter drives the Bio-Wheel. As the Bio-Wheel rotates, beneficial bacteria grow and thrive on its super dense surface. As water flows, the Bio-Wheel eliminates ammonia and nitrite on contact. Bio-Wheel is for all Eclipse, Explorer, Penguin, Emperor and Magnum products.