Feature: 1. Nano quartz balls can successfully reproduce nitrifying microorganisms in a shorter period of time, slow down the water flow, and make it easier for nitrifying microorganisms to be adsorbed in the nano quartz balls and multiply. The more you use, the more obvious the effect. 2. Quickly remove harmful substances in the aquarium, such as nitrate, nitrite, ammonia, etc., while removing harmful substances through parasitic nitrifying microorganisms, it also has a certain adsorption effect, and can quickly remove harmful substances in the aquarium by physical means. 3. High‑efficiency culture, high‑temperature sintering production process, internal voids within 10‑100 microns, very suitable for aerobic nitrifying microorganisms, anaerobic nitrifying microorganisms and other beneficial microorganisms parasitism. 4. Can stabilize the water quality, especially the PH value and GH value on the existing basis of the aquarium, will not cause changes in the PH value and GH value. 5. Ultra‑long life, compact structure, not easy to powder, can be used for a long time, easy to clean and reuse, and the service life is more than 2 years. 6. The high‑density pores bring more surface area and provide a good place for the attachment and reproduction of nitrifying microorganisms . Specification: Item Type: Fish Tank Filter Balls Material: Quartz Ball Weight: Approx. 534g / 18.8oz Purpose: Filtration of Fish Tanks and Aquariums. Package List: 1Bag x Quartz Ball