I have driven past this house! I was in the area a few years ago on business and we drove right past it, turned around and went back to get a few crude cell phone (flip phone!) pictures. I think I still have those pictures on my home computer. I had not noticed the moat/pool from the street.
What I did notice was trash cans at the curbside waiting to be picked up, which looked quite weird in front of a castle. And, there was a sign on the front gate giving notice that it was a private residence, so I assume they do not open it to the public.
-tim