I clean inside that middle 'stem' section probably once every 2 months. Take the whole thing apart once a year. If you dont stay on top ofit it can make the clothes yucky.
ETA- I just clean it with warm soapy water and one of those sponges that are yellow on one side and soft and green and scoury on the other side.
I do the lint filter (where your pond scum was LOL) every month cause my DH works around Drill rigs and his work clothes get covered in a really fine dust that leaves a greasy residue in the tub if it's left to build up. So the lint filter is every month and I wipe the tub down after every load of work gear I do. I also clean where ever there is dust or lint built up, but have never pulled one apart to do it.
I used to clean the top loader filter every wash, or at least once a week. And I cleaned the soap dispenser and washed it with hot water and disinfectant once a month. Now we have a frontloader I clean the trap when I need to as it tells me and its quite a laborious job and wash the water trap often and do a hot water vinegar wash once a month.
When I had a top loeader I would always & I mean ALWAYS clean the filter LOL....I'm very pedantic about my clothes. I love them & don't want them getting crap on them from the filter, so would pull it out & rinse all the muck off with hot water.
Now I have a front loeader that has a "clean me"mode, & its actually recommended every so many washes....so much so that the screen lights up telling you how many washes it's been since you cleaned it & it doesn't go away until you do. I swear it lights up the entire house at night LOL, so it always gets cleaned too. Just add 2 scoops of powder & press clean me........awesome.
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