To provide a decorative lighting system of reduced pressure of water, operable by a small capacity of electromagnet 6, allowing fine regulation by regulating a water level 12 by a cap screw 11 of a water outlet, and capable of obtaining colorful and clear projection.

A wave plate 3 built in with a permanent magnet 2 is provided in a sealed container 1, in a vertical condition by spring pressure of a spring 4. The dynamic pressure of the water is reduced since the wave plate 3 kicks a contact face by a repulsion force caused by homopolarity of an electromagnet 6 disposed in a position symmetric to the wave plate 3 in an outer side of the sealed container 1, and a wave source is located in one portion. A nichrome wire 10 is provided in upper transparent glass, to prevent clouding from being generated caused by a temperature difference between an inside temperature and an outside temperature in the sealed container 1, and a cap screw 11 is provided to regulate the water level. An illumination box 15 for a projection LED 14 is provided in a lower side or an upper side of the sealed container 1.