I've actually never seen that one, remember when it was out, that's about it. Sci-fi is part of the horror genre (aliens instead of monsters, technology or maybe telepathic or empathic 'powers' instead of magic, etc), and while I sometimes enjoy science fiction, horror is just dopey. :^) Reading your post, I do wonder if the salt water thing was an homage (or send-up) when it was used in the movie "Alien Nation".
“horror is just dopey”
oh, “Day of the Triffids” was a VERY dopey movie, simply awful, but back in the day, it looked real-enough to 10 year old kids who didn’t know any better.
and yes, since then salt water has been used frequently as an homage or send-up.