Diplomat APM 8513/2 filter stays full of water and smells?

Is the filter supposed to stay full of water, as no matter how often I clean the machine it seems to smell and leaves clothes bad too. I cleaned it less than a month ago, and ran a machine cleaner through it, and yet again clothes are coming out smelling awful. When you pull the filter out it is full of stagnant water and would perhaps appear not to be refreshing itself during a wash cycle?? The machine is used every couple of days and I am OCD about leaving the door open to allow the drum to dry post cycle once the clothes have been removed...