Instruction: Answer the given question using the supporting document.

Input:
Question: Does it need filters or not?
Document: These Holmes humidifiers are just great...they just wear out every so often when they are used continually during the winter months. I actually believe that as long as you change the filters when they  need it that they enhance your health because you are keeping your nasal and breathing passages moist by keeping the air moist. I get these for both health and comfort reasons and I'm always pleased.
Small and portable. Easy to clean and fill with fresh water. I like the two speed selection. You will need to refill it everyday.
I love this humidifier. It works great. Easy to fill with water and change filters. Love it. I highly recommend.
It is like your kitchen sponge, the stagnant water in the unit and the wet filter is a breeding ground for bacteria. You get 2 filters, but you'll go through them very quickly.
The upkeep is very time consuming - you have to wash it everyday. The filter must be changed every month. Because of this, the cost of filters will far exceed cost of the unit. I didn't even turn it on.
You have to change the filter every month. The filters cost about $10!!! - shipping not included.You have to clean everyday, and then do a major cleaning every week.I have a filter-less (cool mist) one now for years and it is working just as well. The one I have is by Optimus.
I've had this humidifier for about 3 months now, and have been pleased! It does moisturize, but it seem so go through filters awfully fast (about 20 days or so, I think the box says...) I know some reviews say it is loud, but it is good for just white noise, actually. Only on the second setting is it a bit too loud.
We've purchased a few cool mist humidifiers now, and will not purchase another like this. If you look at the replacement filters, which cost around $10/each, they state they last "up to 6 weeks". Yes, weeks. Which means if you buy this for $30, you have to purchase multiple filters for $10 each to use it. What a rip off!!! In addition, these are extremely LOUD when they are on.
Look at the Homedics humidifierHoMedics UHE-CM15 Personal Ultrasonic Humidifier, which is the same initial price. The HoMedics actually is silent (You literally have to look at the lit-up power button to ensure it's on. Or, you can see the continual water vapor streaming out the top, which is also a dead giveaway. But you won't HEAR anything). Also, no filters to buy!
Run time on it is 16hrs filled. Easy to fill tank. Easy to clean. Comes with 2 extra filters.CON's : Slightly loud fan (if you like white noise at night) then this would be a plus :) Would be nicer if it had one more lower level for the fan speed for the people that complain about the slight noise.This product is worth the price! would recommend it to anyone looking into a Humidifier for a bedroom or a living room.
Answer: Yes, a filter is needed.