Features: brand new and high quality Made of macroporous resin material, no recycled materials, safe and efficient. Purify water, remove yellow water & bad smell. Absorb excess nutrients to prevent algae from over-growth. Remove ammonia and nitrite from aquarium water. Filter only, no pouch. Tips: Every 100Liter water need 200g filter media, universal for fresh water and marine water; Before using, please rinse the filter media for about 1minute; Please put the filter media in a mesh pouch, place it where water flows frequently; Please keep the filter media away from fish, to avoid eaten by fish; Soak the filter media in High Concentration Brine for 12hours to make it reusable; Please clean the filter media 1 for time every month. Package Includes: 1 Bottle Aquarium Filter Media Specifications: Material: Filter Media Color: White Weight: Approx.260g (450ml) note: 1.Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!