The Fishmate Pressurised Filters feature the 'Powerclenz' cleaning mechanism (except the 5000 model).
Just turn the dial from 'normal' to 'clean' and the water flow changes direction, back-flushing the filter, and the foam layers are squashed which removes the dirt and sludge.
The dirty water is then pushed out of a second outlet, down the drain or into your flowerbeds.
