In 1992 Disney started TV series based on "The Little Mermaid" movie. In season 1 episode 11 called The Evil Manta (1992) Ariel remembers how she first met Flounder, and the scene is quite different than the scene shown in this movie. In the series she met him when she was still a child, wearing pony tail. Flounder is left all alone and he gets scared from Ariel, but she quickly calms him down and become his friend.
All through out the movie Arista's bangs switch sides of her face between shoots. This goof can be seen best after the subject of taking a friend past the kelp forest.
The pirates on the pirate ship suddenly vanished right when their ship crashes into the rocky shore. With no indication that they abandoned the ship by diving into the water before it crashed.
For the majority of the film, King Triton had outlawed singing in Atlantica. But Marina Del Ray is heard singing a few times in the movie, especially in front of a delivery fish (who could've likely reported her).
In the scene where Swifty asks Triton to raise his right hand for the oath, Triton raises his left hand instead of his right.
Tara Strong is the voice of both Adella and Andrina. Adella has a more normal voice and Andrina has the funny one. At one time in the movie, where Ariel is back from the underground club and tells her sisters about it, you can hear Adella with the funny voice saying: "Yeah me too" and then you hear Andrina with a perfectly normal voice saying "Not without me". They changed voices for a moment.