- Cowboy BeBop at His Computer: All over the place, undoubtedly due to the show being barely seen for a while, as well as 2021's Gag Dub of the show and its Broad Strokes attempt at adapting it.
- Captain Murphy is not the leader of Sealab; Dr. Paul Williams, Marco in 2021, is. Murphy, who isn't a scientist, is there to help with the safety of Sealab. Most decisions on the show involve them working together for the other's expertise, as one would in a real life mission.
- Mrs. Thomas is Ed's mother, not wife. In one of the earliest conversations between Bobby and Ed, he refers to his teacher as "your mother". Paul later talks to Mrs. Thomas when worried about Ed due to this established connection.
- Only Bobby is Murphy's grandson. Salli is just his friend.
- The names of most of the characters are not the same as 2021.(For the rundown: Marco is Dr. Paul Williams, Dr. Quinn is Ed, Debbie Dupree is Gail, Stormy is Hal, & Debbie Love is Mrs. Thomas. The minor Kid-Appeal Character, Jamie, became Dolphin Boy, while Bobby & Sallie were for the most part Adapted Out.)
- Some sources list three "unaired" episodes. These do not exist; three episodes were cancelled before being finished, with no known remnants.
- Due to 2021 using gags from other Hanna Barbera shows, some things are misappropriated to 2020, one of which being clips of Scooby the Seal from Hanna-Barbera's Moby Dick cartoon. Which is odd, given that 2020 did in fact have its own supporting seal character, named Simba.
- No Export for You: This show was one of the few Hanna-Barbera shows who was never exported outside the U.S., which is something especially relevant if you take into account that most of their shows, even those who failed in their own home turf, were broadcast abroad without problems.
Trivia / Sealab 2020