Marineland Replacement Bio-Wheel is compatible with H.O.T. Magnum 250 Pro, Magum 350 Bio-Pro and Eclipse 3.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.
Marineland Bio-Wheel should not be replaced unless damaged. The water flow from your filter drives the Bio-Wheel. Dimensions are 7in Long x 2 3/4in Diameter.