ANS Sinopore Max (10mm) 1kg -Suitable for freshwater and saltwater use -High quality sintered glass rings for serious biological filtration -1L has estimated 1200L/m3 effective surface area for bacteria cultivation, which is 5 times more than conventional ceramic rings. -Neutral material, do not affect pH -Use in trickle filter, top filter, sump filtration, pond filtration, internal filter, canister filter