Micromac UK used to make a ...

Micromac UK used to make a rotating screen which had a vacuum and backwash applied.  The poresize of the screen was selected depending on what was needed to be removed.  If the screen was clean no action was needed.  If the screen started blocking it started rotating and a vacuum system removed the foulants, if the water level rose due to further blockage it brought on a backwash system.  I don't know if they still manufacture them.