the working theory of water-bath air purifier . It siphons the mixture of essential oil and water into the straw , then with high-speed spin the mixture centrifugally spread on to the bottle and form a water layer to resolve the dust and germ in the air . In mean time , the fresh fragrant air blows back to the room . The water became grimy after whole day use in dusty place .It adds moister in the roon with air condition. Improve immune system and increase habitus . If put the liquid , vinegar concentrate into didinfecting in water , water-bath air purifier can kill epiphyte , bacteria quickly , and also it can be guarded against respiratory disease effectively .