Specifically designed for Fluval Spec Desktop Aquariums BIOMAX provides critical stage 3 biological filtration. BIOMAX\'s large surface area provides optimal colonization of beneficial bacteria which enhance the elimination of fish wastes resulting in a healthier aquarium environment. Key Features: - Specifically designed for Fluval Spec Desktop Aquariums -Provides critical stage 3 biological filtration -Large surface area provides optimal colonization of beneficial bacteria -Enhances the elimination of fish wastes resulting in a healthier aquarium environment -60 g (2.1 oz)