The cleaner has three containers. The first contains the cleaning solution, which you need to fill to the recommended level. The second compartment takes clean hand warm water. The third compartment holds the mucky water sucked up from the cleaning process. Each of the containers is easy to remove and empty or fill. The detergent is automatically diluted by the cleaner, so no messing around with measuring jugs. It is possible to apply pre-treatment for stubborn stains, with a spray wand that plugs in the side of the cleaner. This does mean that you have to empty the detergent container and fill with the pre-treatment. This is a bit of a pain. I found it easier to put a little pre-treatment on a cloth and gently dab it on the stain.