Marineland Penguin Bio Wheel Assembly Replacement for the NEW Penguin 100B Power Filter. Note that the Bio-Wheel should only be replaced if damaged. Discoloration of the pleats is normal and indicated proper functionality. The Bio-Wheel spinning at any speed is still working to eliminate ammonia and nitrate, and irregular rotation is normal.
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.