A staff favorite! This diffuser runs constantly on one fill of water for roughly 12 hours straight. It gradually changes colors between 7 different ambient lights. When it is empty it flashes red to let you know that it’s ready for more water. You can have it cycle gradually through all the colors or select one favorite color for it to stay on. If you choose to shut the lights off and still have it diffuse, that is possible also. When it is empty, it will flash to let you know. It is extremely easy to fill with water and its motor is silent.