The two liter container of Eheim Substrat Pro Biological Filter Media is the perfect addition to any filter basket for freshwater or saltwater ecosystems. The media is a highly porous filter material made of splintered glass, and provides a surface structure with a colonisable area of approximately 450 m² per litre and offers excellent colonisation conditoins for essential purification bacteria. This standard bio-filter medium is washable and can be reused after thorough cleaning.
Never clean or change all the filter media together in one operation, and never clean too thoroughly. The bacteria culture must not be completely destroyed, otherwise recolonization will be compromised.