Waterfall of sand *Material:Resin *Size(cm):25*16*28 *Nature look,can be installed anywhere in the Aquarium. *Rock style.Natural looking with our PU background board. *Should be using the air pump to make the sand flowing. The air pump must be adjustable. *Organic waster should be removed from the collection tank at regular intervals to keep the water cleaner longer , as well as promoting necessary beneficial bacteria and reducing odors associated with decaying waster. *Ideal decorations for any type of aquarium decoration. *Not provide air pump Installation Instructions: 1.Fix the position and make the water do not over the whole product to prevent the sand overflowing. 2.Using the adjustable and high flow air pump 3.Turn on the air pump, put the appropriate sand into the sand cup slowly. (because too much sand will block the hole, but too little is not good for landscaping.) As different air pump has different performance, pls pay patience to make it workable. Thanks!