1、SAFE MATERIAL: Aquarium filter media bio balls are made of zeolite and nano quartz balls, without harmful additives, ensuring safe and reliable filter media. 2、MULTIPLE FILTRATION: The porous structure of the filter media can adsorb various impurities and filter tiny particles to ensure clear water. 3、DURABLE DESIGN: Fish tank filter media bio balls have a long and stable service life, no need to change the filter media often, saving time and effort. 4、EASY TO CLEAN: Aquarium filter media balls are easy to clean and can be used repeatedly, and help reduce the growth of scale and bacteria. 5、WIDELY USED: Aquarium filter media zeolite balls are suitable for all types of fish tanks and aquariums, one box can be used for 25‑45cm/9.8‑17.7in fish tanks. Item Type: Aquarium Filter Media Bio Balls Material: Zeolite Product Weight: 500g/1.1lb 49 x Filter Media Balls 1 x Storage Bag Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.