Shady Shoals is an underwater retirement home for elderly sea creatures. Mermaid Man and Barnacle Boy reside here. Some activities here include television, playing chess, rocking on chairs, sleeping, playing Bingo, and other activities. It was destroyed in Mermaid Man vs SpongeBob when Plankton went there, controlled the minds of Mermaid Man and Barnacle Boy, thus making them evil resulting in the home's destruction. It is located in Conch Street.
The Shady Shoals Retirement home appears like an average retirement home. It has a large cafeteria which people eat from, showers, and bedrooms. It is well furnished and has many places of interest. The exterior, though, is very average appearing like many other homes found in the undersea community.
- Old Man Jenkins
- The other Mable from "The Two Faces of Squidward".
- Mermaid Man
- Matt Liebl
- Barnacle Boy
- Miss Shell
- Unnamed, old bearded man
- Willie Jenkins (the old man that's orange who is confused to be the man who appeared squirting ketchup on SpongeBob in the episode Picture Day and also he is Old Man Jenkins brother)
- Frankie Cornele (man who appeared on Mermaid Man and Barnacle Boy standing behind Mermaid Man when he was at the water fountain)
- The Manager
- Unnamed Nurse, "Gramma's Secret Recipe"
- Unnamed Lunch Man, "Mermaid Man and Barnacle Boy"
- The Shady Shoals first appeared in the episode Mermaid Man and Barnacle Boy.
- Shady Shoals appears in six episodes.
- There used to be another rest home in Bikini Bottom (The Rusty Krab), but it was bought by Mr. Krabs and converted into Krusty Krab.
- For some reason,it was repaired in Shuffleboarding.
- In Doing Time Shady Shoals appeared without Mermaid Man or Barnacle Boy.