It’s hard to imagine this animated movie being made anytime but the eighties. The concept feels like it was pitched as, “What if you took the Smurfs and put them under the sea for viewers who watched MTV?” And that’s pretty much what you get: characters similar to the Smurfs, though they do more than just sing a repetitive song, living in an underwater setting with bright eighties-style visuals. It's easy to see how appealing this would be to children.

Source on TMDB