I have no idea what would keep raccoons out, as they can be very crafty. I would think some heavy duty material would suit your needs better. Maybe stainless steel meshing could be an option depending on what you want to spend. That could get very pricey hough, and you'll want to save your money for the pond equipment alone, and possibly some valuable fish if you are into show quality types. Do a search on "pond covers" or "protecting outdoor ponds", and you may find something useful. You could even protect the filter/equipment by building an outdoor housing unit for it, possibly using wood, or one of those durable thick plastic tubs to contain it and close up to prevent tampering. Hope my advice helped.~Angela