Instruction: Given a question and the related document, and generate the answer to the question based on the information provided in the document.

Input:
Question: How do I replace the dirty water tank?
Document: It really cleans so well, and it picks up all the dirty water easily. The floor is squeaky clean.The dirty water is in a separate tank, of course, and it is very easy to clean. I do keep a supply of replacement filters on hand, because of how stinky mine can get. They are small, inexpensive, and last a while. The only reason I have to finally replace is that the machine finally fails to pick up the dirty water.
There are replacement parts (also inexpensive) that are replaceable, but for me, it's worth it to just get a new one because I use it so much. The actual motor has never quit on me.One thing I have seen people complain about in reviews is that it leaks or doesn't pick up the dirty water. I have experienced this briefly but it was when I didn't have the dirty water tank back in there correctly. If you replace the small filter, it also has to fit in just right.
The tank has to snap back in just right. Yes, I replace the clean water a few times when cleaning...all my floors are tile, but it doesn't bother me to do that as my floors are SO clean. I also have no problem emptying the dirty water a few times. Both tanks are lightweight and easy too use.I highly recommend this floor cleaner. I don't see how anyone could be disappointed at all.I am updating this floor cleaner review March, 2014.
I've been using FloorMate since 2004. I have had to replace it about every 3-4 years. I'm currently on my 3rd one. Every one of them ends up leaking clean water from the solution tank and dirty water from the holder tank. Don't know why this is, but I've come to expect it after a few years of use. I have a 3600 sf house with a lot of hard floors, so I don't mind having to buy a new every few years.
Pros:-cleans well, the tank lets you know it's getting everything up!-don't have to wash pads-can use your own cleaners and regular tap water-has nice long cord-doesn't leave wet or white "cloudy" residueCons:-takes a long time to do (have to keep refilling and emptying the tanks)-heavy and still strenuous on your body/back-might have to eventually replace bristles or parts-heavy to lug up stairs-hard to reach corners due to size of head
*I have used this product for over 15 years. I continue to replace it when certain plastic parts break. There are no similar tile cleaners at this price. It sucks up the dirty water which a mop will not do.I found out recently that Hoover will no longer be making this product and there is no replacement.
This is an awesome product! I have had this product previously and used it for many years before needing to replace it. I LOVE that you can mop your floors with clean water and the machine picks up the dirty water. You will never clean with dirty water again if you use this. I can't stress enough how clean your floors will be!!!
I was in disbelief at how dirty my floors were and how awesome the Floormate cleaned. As matter of fact, when my son started crawling, I decided to have the tile deep cleaned, but the company that came out told me to wait because my floors really were not in that bad of shape! Wow, thanks Hoover!After a couple of years my Floormate started leaking and it was time to replace. I bought a combination Bissell. The Bissell was going to help me clean my carpet and my tile.
The dirty water reservoir tank will not latch into place. I think there is a part missing. Have not been able to use it.
If your floors get particularly grody like ours, cleaning the dirty water tank can be pretty nauseating too but that's all a part of cleaning I suppose.
Answer: It pops out through the use of a lever and you can dump the waste water.  The waste tank is small enough that it can be washed out easily.