Rainbow Fish is a children's animated television series adapted from the book of the same name by Marcus Pfister. However, the television series does not follow the plot of the book; instead, it takes the character and the setting to create new stories. For the show's purposes, some characters were added and others were expanded. In the series, the fish live in a place called Neptune Bay (named after Neptune, the god of the sea), and attend "The School of Fish." The series also features a location called "Shipwreck Park," resembling the wreck of the RMS Titanic.

The series was produced by Decode Entertainment and EM.TV & Merchandising AG for Sony Wonder. It originally aired for a single season of 52 episodes, from January 8 to December 24, 2000.