Revealing mistake: The algae in the "garden" is fake. It is cloth.
Cabin by the Lake (2000)
1 revealing mistake - chronological order
Directed by: Po-Chih Leong
Starring: Judd Nelson, Michael Weatherly, Hedy Burress, Susan Gibney
Continuity mistake: After the dummy is in the water with the camera and the killer comes back to check on his "garden", we see the dummy from behind while he's swimming towards it. His hair barely moves. Then we see the dummy from the front and the hair is flowing freely in the water like everyone else's.
Banner in the back of Stanley's van: I'm the guy your mother warned you about.