Check the listing for details. SEACHEM TIDAL 55 MATRIX 250 ML FILTER MEDIA to CONTROL AMMONIA. Condition: New. Listed at 13.25 USD. SEACHEM TIDAL 55 MATRIX Listing is for ( 1 ) : SEACHEM TIDAL 55 MATRIX Replacement Matrix for Tidal 55 Power Filter Treats up to 55 gallons of waterThis is an excellent high capacity biofiltrationControls ammonia, nitrites & nitrate levelsThis improves your aquarium water qualitySuitable for freshwater & saltwater set-ups Improve your water quality with Seachem Tidal Matrix high capacity biofiltration, which controls the ammonia as well as the nitrite and nitrate levels in your freshwater or saltwater aquarium. Biofiltration is important because it acts as a substrate which allows microorganisms to grow. Please feel free to contact me for International and combined auction shipping rates or with any questions or concerns that you may have about my products. Thank you !