is a Japanese manga series written and illustrated by Kiyomi Sugishita. It was initially serialized in Shinchosha's seinen manga magazine Go Go Bunch from April 2017 to February 2018. After the magazine was discontinued, it was transferred to the Kurage Bunch website in March 2018.
The series is set in an aquarium that is 200 meters below Tokyo Bay called "Magmell Deep Sea Aquarium". It is centered around Kotaro Amagi, a young boy who is a fan of deep-sea creatures, has started working a part-time job as a cleaner in the aquarium.
Written and illustrated by Kiyomi Sugishita, Deep-Sea Aquarium Magmell was initially serialized in Shinchosha's seinen manga magazine Go Go Bunch from April 8, 2017 to February 9, 2018. After the magazine was discontinued, it was transferred to the Kurage Bunch website resuming serialization on March 9, 2018. Its chapters have been compiled into ten tankà Âbon volumes as of April 2025.
In February 2026, Yen Press announced that they had licensed the manga for English publication, with the first volume set to release in August later in the year.
The series was ranked fourteenth in the 2019 edition of Takarajimasha's Kono Manga ga Sugoi! guidebook of the best manga for female readers.