Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: How hard is it to clean the inside of the unit?
Document: 2. There are three buttons on the front of the unit.. On/off, % of humidity, fan speed. The writing next to the buttons is very small and hard to read. 3. The biggest issue is it's very difficult to see how much water is inside. You have to use a flashlight and hit the water at a certain level to see it. So far so good. At this point I'd highly recommend this unit.
This is the worst humidifier design. I love Essick brand, but this design is hard to fill, hard to clean, doesn't seem to hold that much. After I finally got tired of complaining everyday, it was too late and too expensive to return. So now I have an expensive, plastic plant stand!! !
The fan blows air over the wet wick and disperses moisture into the air. Very simple, very clean.And finally, while the case looks nice and has nice lines, it is cheap brown plastic, but the 12x12 decorative stone on top gives the unit some nice pizzazz. For me however, this unit is more about the job it does, than the way it looks. It is a workhorse.
This is my 3rd season with the Essick humidifier.Works great and keeps my humidity around 35% at a setting of 3. Purchased at a local home center along with a spare filter, this year the filter was hard to find so I checked out Amazon, glad I did.Don't know why some people are have having filling issues. All a person has to do is add 3 gallons when the unit stops for lack of water.
I contacted the company about the broken stone, and they were relatively quick about sending out a new one, so that was one upside. Also, the unit does do its job, it runs when it's supposed to, and keeps the humidity in the house at a healthy level, and it's quiet as long as you don't turn the fan up past level 5. But for the price, I expected better quality, so I'd be hard pressed to recommend this unit to anyone.
It lifts off very, very easily. For changing the wick, it is also easy, just lift it straight up out of its guides and slide in a new replacement. Do take extra care with your stone that you don't break it.Well, I think I've hit the hi-lights and can say with 100% certainty that I highly recommend this humidifier. If you are not too picky about its looks and about hearing a fan run, you will love this unit and its function. Clean and easy.
The unit itself is made of plastic, flimsy in my opinion. There is a float inside that attempts to tell the display when the water is low, and that doesn't work all of the time, sometimes it just says it's empty even when it's full, so I had to tape the sensor inside up in this case, so the unit just thinks it's always full, and I check it periodically.
It is much better than using tanks. Next, (this is the best part), MY EP9 500 has a LIGHT inside of it. IT WORKS AMAZING!!!! This light enables you to see the MAX FILL line on the wick assembly when filling. It is very easy to look in the door and see when the humidifier is full. There is only one downside to the light - it stays on all the time, even when the unit is turned off.
No more waking up to dry eyes, noses, & throats.I can't believe people are complaining about refilling it. Use a pitcher! The unit tells you when it's empty on the display so you just Convert Gallons to Liters. Hint:  It's 3.5 sun tea pitchers. If you want to check the level you want to turn on a light in the room & just look inside for the Max Fill line. Nothing complicated about this unit.This humidifier is stylish & functional! &#60;3
I use a small flashlight to shine inside the door so I can see where the water is up to relative to the fill line. That is a poor design.Overall, I like the unit, and am making my own adjustments to &#34;perfect&#34; it. I am working on a small clear hose to make it easier to fill from a nearby faucet. Also working on a float to put inside the reservoir to make it much wasier to see the water level.
Answer: Easy!  Just lift the main unit off the base and the base unit is exposed for easy cleaning.  Just lift the cage out off the base that contains the wick and go for it.  The instructions recommend weekly cleaning and sterilizing.  Two of the 3 units I have  purchased this season have reached 750 hours of operation when "CF" check filter) appears on the readout.  I opened both units and determined that there was no reason to do a deep cleaning at that time.  I add a few caps full of bacteriostat  to every other filling to keep mold and mildew out of the unit.  If you have hard water, the wicks will harden with mineral deposits quickly and will need to be replaced.  I have hard water and have not yet felt it necessary to replace these wicks.  They are fairly cheap at around $13 each (1 per unit).  I am hoping to get a full season out a wick.  Hope this helps.