Instruction: Generate an answer to the question by utilizing the information contained in the document.

Input:
Question: Does it need filters?
Document: I 've had 2 of these for over a year. They work great, are quiet, stylish and require no wick or filters. Mist is adjustable, night light you can turn on or off. Has fragrance diffuser bottle. It's nice to have a simple humidifier that you don't need wicks and filters to use. Safe to use around kids & pets because it doesn't heat. It uses cool mist. The description says white; mine is an off white cream pearl color. Very nice.
So far that seems to be enough to handle our bedroom at night, which is all that I need it for. In doing this I haven't had any spills, leakage, or residue at all. I can't speak for the higher levels. So far, a very happy customer!
I don't want or need the night light and am very happy that it is controlled separately so that I can leave it off. The indicator light is bright but not so much that I need to cover it (unlike my last unit, Medisauna, which lit up the whole room).
After arriving very quickly during a time of illness and sudden need for a humidifier that was quieter than the one I picked up at a local store in my hour of need. I am quite pleased - after two weeks of use - with the SPT SU-2550 Ultrasonic Humidifier.
This humidifier works extremely well. It is silent and easy to operate.For those customers who have complained about having to refill it too often - there is probably no need to put it on the highest setting - I have one in my large great room, and I keep it at just above the half-way setting. I fill it twice a day (morning and evening), which is really no burden.
I find that I can tilt the tank over the base to drain most of this water, then place a small towel under the tank when carrying to prevent dripping across the floor. Given all the problems I've had over the years with various humidifiers, I feel this need for a towel is a small price to pay for an appliance that does exactly what it is supposed to do - put moisture into the air. Plus it looks better than most units.
I am so impressed by this humidifier. It works great and is so pretty that it can pass for a type of lamp or something. I use mine every night during the colder months. Indoor heat dries out my sinuses terribly. I also bought some essential oil for use in the diffuser which is nice. You can select how much humidity you want with the dial. For a large bedroom, you'll probably need it on full volume.
After running all day and night the towel is totally dry.This unit is easy to refill with a removable screw in open/close knob on the bottom of the tank. I do see that this will be an item that needs some upkeep on the tank. You will definitely need a bottle brush to be able to get inside and keep it clean as it does have some nooks and crannies.After only one days use I can say I am pleased with the unit.
Graceful shape and quiet when on low  - can hear slightly when on higher settings, not bad.Easy to fill and set  up but will need a long handled botttle washer to thoroughly clean. Fairly small footprint.Overall very satisfied with cool mist output throughout the night and  even longer when on low setting.Have not used aromatics yet. So far working without any problems over the last month.
we were disappointed--even on the medium setting, water collects on everything around the humidifier. also, i find the fragrance diffuser to not emit a strong enough scent for my liking. but for $30, what could i expect? on a positive note, the night light looks nice, and my 3 year old loves it!
Answer: It doesn't use filters.  Pretty simple to use!