Combination of water and sound. When properly used, the water begins to create special structures that may resemble some crop circle formation.

On a YT person with a username Brusspup presents a video with an experiment in which he let a stream of water flow from the hose in front of the loudspeaker, which transmitted a sound of the frequency 24 Hz. Water subsequently began to form structures resembling a sinus or rather a spiral.

This phenomenon is associated with acoustic levitation. So if you use the right frequency spectrum, any object can be levitated. In the laboratory conditions, small objects have now been levitated. However, it is a principle and it works!