Make A Pond Vacuum What Is A Good Pond Vacuum?

What is a good pond vacuum? - make a pond vacuum

Me and my dad r trying to make a Vacum Rilly for your pond is large. is 60 meters by 30 meters. We have a large amount of silt on the floor of the same. Which has a filter, but dose not capture everything. WE R attempts to provide clean plz help THX