QUALITY: Aluminum alloy CO2 aquarium atomizer, nickel-plated after oxidation treatment, acid and alkali corrosion resistance, durable. FUNCTION：The diffusion plate decomposes the CO2 into tiny bubble streams, dissolving it in water, then allowing plants to absorb CO2 for photosynthesis. HIGHLY SEADLED: Be sure to tighten top threaded port, press suction cup tighetly to fit the surface of fish tank side wall tightly, to achieve the best atomization effect. EASY to TO CLEAN: Open the upper diffuser cup cover to replace it. It is recommended to clean once a week to avoid bacterial growth. Installed directly under the aquarium. -U-shaped design is more convenient than ordinary filter tubes. -The length can be adjusted freely according to the height of the the aquarium. Note: The data is manual measurement, please allow 1-33cm error, due to differences between light and screen, there will be some color difference, the specific received in kind prevail.