Dumbest Aliens movie ever!!

Rating: 10/10 (20 January 2005)

In The Pivotal Final Scene, Our Hero's brother splashes water on the alien, killing it. The aliens have an Achilles Heel: water is like acid to them.
Take a look at a map of the Earth. What do you see? Water! 75% or so of our planet is covered in water. It's in our air, in the rocks, in all the plant life. Would you consider invading an alien planet that was mostly, say, sulphuric acid? I think you'd either find a protective suit or check your starmap for the nearest other invadable planet. It's just plain silly to think that aliens who die when contacted by water would invade us.
Worse, and I mean really worse, they invade because they are harvesting us, presumably to eat us. We are actually over 80% water! One bite and it's bye-bye alien.
This bit ruined the movie for me. It's such a glaring plot hole that, in my opinion, it just negated anything else that might have been positive in the movie.