[1] The series is a combination of the sketch comedy, edutainment, and musical genres, and revolves around the underwater adventures of a group of merperson preschoolers named Molly, Gil, Goby, Deema, Oona, Nonny, and Zooli.

[3][4] On February 19, 2020, the show was renewed for a sixth and final season, which premiered on October 19, 2021.

One of the guppies may go to a shop that mostly focuses on the theme (example: a doctor's office in "Call a Clambulance!").

At lunch, three of the characters make a food pun about the subject of the episode; usually done by Nonny.

After the sketch, some classroom activity is shown further reinforcing that episode's topic, or Mr. Grouper talks more about the theme.

Outside the classroom, the guppies act out a story about the theme, interfused with Adobe Flash-animated graphics.

The episode concludes with a final sketch by Gil and Molly, followed by a shorter version of the theme song.

Gil and Molly simply introduce themselves before the theme song with no opening gag.

The show cuts right to school after the theme, and the dance songs and field trips were removed.

With the exception of select special episodes, Mr. Grouper's overall presence in the show was primarily reduced to the beginning class segments.

Gil and Molly's sketches were removed as well, instead having Mr. Grouper wave goodbye to the viewer as the guppies go back inside.

Heavy metal singer Ozzy Osbourne guest starred as Sid Fishy in the 2015 episode "Super Guppies!

",[6] while actor George Takei guest starred in a sci-fi mashup which pitted him as a Darth Vader-like armored villain against starship captain Gil and his first officer, Mr. Smart (Nonny).

Recurring character Mr. Grumpfish is a reference to Monty Python's The Meaning of Life, while the episode "The Puppy and the Ring" makes in-jokes ranging from J. R. R. Tolkien to L. Frank Baum.

The series was created by the duo of Jonny Belt and Robert Scull, who had previously served as staff writers and executive producers on another Nickelodeon animated series, The Backyardigans (2004-2013), created by Janice Burgess.