Eheim Substrat is a biological filter media which is ideal for use with the AquaBall, Classic, Ecco and Professionel range of external filters. It has been specifically developed to provide the best site for bacterial colonisation.
Biological filtration is created by bacterial colonies that develop on a surface. This media is made of sintered glass which provides a highly porous surface, which gives bacteria firm holding ground. The bacteria filters the water as it passes through for the cleanest finish. Ammonia and nitrite are converted into non-toxic nitrate.
It can be washed and replaced. But this must be done sparingly so as not to disturb the delicate bacterial colonies.
Suitable for fresh and marine water.