An external docking station may be provided and may a filter manipulator that is arranged to (i) input without human intervention, a filter into a pool cleaning robot that exited a pool and is located in a filter replacement position and to (ii) assist without human intervention, in positioning the filter at a position in which the filter is at least partially disposed within a path formed between a first fluid opening and a second fluid opening of a housing of the pool cleaning robot thereby allowing the filter to apply a filtering operation when fluid passes through the fluid path.