This is a fantastic diffuser that last all day or all night long. In fact it will almost last 20 hours on the lowest setting. I am very happy with the mist flow since you have the option of how fast or slow you want it. At night when I need the moisture for my sinuses, I always have it on the higher mist setting and it lasts all night helping me sleep. I even occasionally use the lights at night to enjoy watching while I fall to sleep.
The humidifier is easy to add water to and is simple to use. It is important that you do not fill the water over the fill line, or it will not mist as well. When you are placing the lid back on, make sure the front of the top is facing the front of the bottom and it will slide into place easily.
On the front of the bottom of the diffuser is the control knob and light button. You can use the light as a night light without even adding water if you want too. When you turn the light on, it will start to rotate slowly between the colors. There is a small band around the bottom section, a window up the top section and the whole top of the diffuser that lights up when the light is turned on. If you do not want it to rotate colors, you can press the light button until you find the color you want it to stay on.
The Exqline 1500ml Aroma Essential Oil Diffuser holds almost 1/2 gallon of water and lasts a long time. In the lowest position it can last up to 20 hours and in the highest position it can last up to 10 hours. I really like having the mist options on the diffuser since it is a knob and you can turn it to adjust the mist as needed. The higher the mist, the shorter time it will run. It will also shut off by itself when it runs low on water.
This diffuser is perfect for any size room. If you want a fragrance, just add several drops of 100% essential oil to the water. If you want to use it only as a humidifier without fragrance, then don't add essential oil.