[Natural Material: Hamiledyi natural materials used in our aquarium filter media bio balls are sturdy and durablecan effectively absorb particles and debris solve the problem of muddy water and stabilize the water quality of the aquarium "Product Details: Package includes 4 packs filter media bio balls. It has about 500 grams (1 pounds) fish tank filter media in a mesh bag. All biological filter media are packed in an ordinary plastic mesh bag (Its not a filter bag). Before use please rinse with water and then put it in the fish tank or filter" Easy to Clean: Put these filter balls them in your filtration system and rinse them regularly to keep them in top working condition. The lightweight design of our bio balls makes them easy to handle and with durable mesh bags they make maintenance a breeze Widely Used: Our bio balls for aquarium filters are suitable for most filtration systems the bio-balls can be used in a variety of filters such as canister filters pool filters hang back filters and so on. With our bio balls you can enjoy a beautiful and clear aquarium Warm Reminder: When the product is updated the filter media such as aquarium ceramic ring and bio ball may be slightly changed. Before use it must rinse with clean water first it is very important]