Feature: 1. Hydrophilic biological material, biomimetic elastic cells, strong adsorption, specially designed for the enrichment of nitrifying germ. 2. Combining 4 kinds of nano‑functional materials, it has the effects of softening water quality, providing beneficial trace elements, adjusting PH value, and strengthening the activity of mycoderm. 3. Simultaneously process ammonia nitrogen, nitrite, and nitrate, reduce water exchange (requires the corresponding process and adds more filter materials). 4. 3D elastic cells, no powdering, no clogging, no slag drop, no alkaline substances. Cultivate and solidify germ and make them grow rapidly. 5. High‑quality resin, peg polymer and cellulose material, suitable for fresh water and sea water. Specification: Item Type: Aquarium Filter Media Material: Resin, PEG Polymer, Cellulose Product Color: As Pictures Shown Product Weight: Approx. 71g/2.5ozInstructions for use: 1. For the first use, it is best to soak and clean with clean water once, or it can be used directly in the filter tank. 2. Place this product after physical filtration, and place it comfortably without squeezing forcedly. 3. Start up the new tank: Use the conservation water, please make sure to sprinkle the fresh nitrifying germ on the product, and you can put fish in the water for up to three days. In terms of daily use, if you update other filter materials, please complete the replacement twice in three days. 4. Routine maintenance: Please clean the filter material once every six months to a year, half of each time, 3 days apart, gently wash in clean water or machine wash.. Package List: 4 Pack Aquarium Filter Media