- Casting Gag/The Danza: Idol Singer and voice actress Kaya Mizuki is voiced by Idol Singer and voice actress Nana Mizuki.
- "Do It Yourself" Theme Tune:
- The ending song "Konpeki no al Fine" is sung by a group called "Izu no Kaze", comprised of Yuuma Uchida (Iori), Ryohei Kimura (Kouhei), Hiroki Yasumoto (Shinji) and Katsuyuki Konishi (Ryuujirou).
- Episode 11 features another version of the ending sung by Nana Mizuki (Kaya Mizuki, who is the one who sings the ending theme In-Universe).
- Real-Life Relative: Iori is voiced by Yuuma Uchida, while Nanaka is voiced by his real-life older sister Maaya Uchida.
- Relationship Voice Actor:
- Iori, Azusa and Ryuujirou are Rock, Love Heart and Maxima.
- Shinji, Ryuujirou, Kudou and the Head Bartender are Sado, Hisagi & Kengo, Yumichika & Mizuiro and Aizen.
- Kaya, Toshio, Shinji, Kudou and Kouhei are Hinata, Shino, Han & Roshi, Toneri and Shizuma.
- Toshio, and Shinji are Hanai and Tougo.
- Aina and Kudou are Taneshima and Takanashi.
- Nojima, Kudou and Ryuujirou are Kon, Mariandale and Konitan.
- Mitarai and Yamamoto (Junya Enoki) are Taichi and Takeru.
- Mitarai, Iori and Ryuujirou are Kaneki/Haise, Shirazu and Amon.
- Azusa and Yamamoto (Jun'ya Enoki) are Scarlett Witch and Spider Man (Japan Dub).
- What Could Have Been: There might not have been an Animated Adaptation at all; back in 2017, it was implied on Twitter by series creator Kenji Inoue that due to the heavy drinking aspect and certain characters being under-aged in the Manga* , it was going to be impossible for an Anime of Grand Blue to occur. While it ultimately was adapted, all characters who do drink are forced to be at least 20-years old, so that Moral Guardians wouldn't make a fuss about anyone drinking under-age.
Trivia / Grand Blue