Features: 1.Adding Activity: Fish tank bio balls with nano sized negative ions produce an electrolytic effect on water, making water molecules smaller and penetrating cell membranes to increase cellular activity. 2.Improves Water Quality: Aquarium bio balls are used in fish tanks or aquariums to fully filter and purify the water and to improve the quality of the water. 3.Excellent Living Environment: Fish tank filtratlon material distinguishes impurities, stabilises PH and creates a good living environment for fish. 4.Applicable: Aquarium biological filter media is suitable for top filtration, bottom filtration and external filtration of fish tanks. 5.Superior Quality: Aquarium bio balls does not drop slag or muddy water. It is fired at high temperature, hard and firm, and will not powder when placed in water for a long time. Specification: Item Type: Aquarium Bio Balls_x000D_ Material: Nano Bacteria Ball_x000D_ Use: Aquarium and Fish Tank Filtration_x000D_ There is 0-5g/0-0.2oz Error PackageList: 1 Bag x Aquarium Bio Balls