This versatile product does not require special fog fluid and replaces that messy dry ice in many applications.  Just place the diffuser, in a few inches of clean water, plug in the transformer and a  fog/mist will immediately begin to roll off the waters surface. This is not smoke it is real fog. A perfect match for the Halloween witches pot. or place it in a beaker of  water to create a nice effect in your laboratory. This product has become very popular for use in fountains and other water displays. It doubles as a room humidifier and will help keep sensitive exotic plants watered. The unit requires about 3 inches of water depth, minimum, (to use in deeper containers just place something to bring it up to about an inch and a half from the surface.)  Includes key to open the unit for periodic cleaning of the sonic disk. Replacement disks available.