Quite a complete game for a game jam with a lots of attention to details!
The plug cables mechanic is very original, and the 5th level start to exploit it pretty well. I like how they glow when plugged. The fish controls are a bit uneasy but since it's not a precision game that nice. I like how the eyes of the lil' point in the direction where you'll go.
The neon with scanlines easthetics works very well, and the music is good on its own, but also fitting the theme quite well.
I don't really get how it matches the theme gameplaywise though, even if in the narrative it is clearly stated.
Congrats making it all in pure JavaScript!
P.S.: That may be a nice idea to put a disclaimer to warn kids to never put electric cables underwater