THE FUNCTION OF AUTOMATIC ADAPTATION TO WATER LEVEL: this product is designed to protect and manage duckweed in the aquarium. A Duckweed fence can automatically adjust its height according to the water level, making the fence on the of the water all the time. THE FUNCTION OF PROTECTING FLOATING PLANTS:the fence can separate duckweed into different areas to prevent duckweed from being washed away by the strong flow of the filter, drawn into the filter, or eaten by fish. The fence can protect duckweed from being or destroyed, which is conducive to maintaining the environment balance in the aquarium. THE FUNCTION OF IMPROVING WATER QUALITY IN THE AQUARIUM: duckweed fence can prevent the water quality of the aquarium from becoming muddy by the strong flow of the filter. This product can also prevent aquatic plants from blocking the filter, which could affect the filtering effect. Based on these, this product can improve the water quality of the aquarium and protect the health of fish. THE FUNCTION OF DECORATING THE AQUARIUM: the design of the floating plant fence is exquisite, which enhances the beauty of the aquarium. Different areas can make duckweed present in different ways and colors, to build an interesting and rich aquarium environment. BEFORE USE, PLEASE CLEAN THE OF THE AQUARIUM CAREFULLY; and then put the sucking disc and hose into hot water which can twists and deformations caused during transportation to make them soft and easy to install. Colour:black Material:plastics Package Contents: 2 set x floating plant corral Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.