WATER FILTERS, ESPECIALLY FOR AQUARIA, TERRARIA AND GARDEN PONDS, AND MADE OF OPEN-PORED SINTER GLASS OR OPEN-PORED SINTER GLASS CERAMICS

open-pored sintered glass and open-pored sintered glass ceramic materials for use as substrates for microorganisms, as biological filters in fishtanks, and for biological purification of drinking water

open-pored sintered glass and open-pored sintered glass ceramic materials for use as substrates for microorganisms, as biological filters in fishtanks, and for biological purification of drinking water