Premium Natural Bio filter Support Media For Controlling Ammonia Nitrite And Nitrate In Freshwater And Marine Aquaria;Highly Porous Media Designed To Provide Exceptionally Efficient Bio filtration For Single Site Removal Of Ammonia Nitrite And Nitrite;Each liter of Matrix provides over 170 square feet of surface equivalent to over 10 gallons of typical plastic ball media;Matrix May Be Placed In Any Kind Of Filter And Is Particularly Effective In A Canister Filter;250 Milliliters Treats 25 Gallons