EHEIM Substrate Pro: Biological filter mass for optimal biological decomposition.

After the mechanical treatment of water by EHEIM MECH, the PRO substrate provides significant cleaning bacteria the best colonization conditions by the high density of the spherical shape (full volume exploitation) and the ideal surface structure (maximum number of bacteria on each sphere). This combination has the maximum number of cleaning bacteria that ensures clear and healthy water and stable water conditions which allow a longer duration of use of the filter. Pro substrate reduces nitrites pollution points, it is washable and reusable