Description: 【Noise Reduction】: This aquarium outlet effectively reduces noise at the water outlet without affecting water flow. It prevents foam splashing, minimizes buildup, and helps maintain a clean aquarium environment 【Enhanced Oxygenation】: By utilizing the impact of water, this connector keeps bubbles circulating within the water column, making it easier for oxygen to dissolve into the water for improved aeration 【Compatibility and Dimensions】: The aquarium water outlet with an inner diameter of 20mm, suitable for aquariums with an outlet diameter of 20mm or 25mm that use bottom filtration, back filtration, or external circulation tanks 【Gentle Water Flow】: Ideal for aquariums with sand as it provides gentle water flow that won't disturb small fish or displace sand 【Installation Guidance】: Ensure to follow the product's indicated water level line during installation. Incorrect water levels can lead to increased noise if too low or potential backflow during power outages if too high   Specification: Material: PP   Size Chart: Inner Diameter 20mm/0.79inch Package Includes: 1 Set Fish Tank Water Pump Filter Water Outlet Note: Please allow slightly errors due to manual measurement and different monitors.