Insanity on the Sea - Recommendations

Alt title: Koko wa Kurutta Umi no Ori

Insanity on the Sea

If you're looking for manga similar to Insanity on the Sea, you might like these titles.

Aoi Umi no Sashimi

Aoi Umi no Sashimi

Nagisa has just recently transformed from being a human to a mermaid and is easing into the transition of living in the ocean. But when she crashes into a research submarine, she loses her memory and is brought on board the Sogei. It turns out that her love interest from when she was still human, Osanai, is on board and he tries to keep his past with Nagisa a secret from everyone else. Her mermaid friend, Tsunami, goes on a rescue mission to find Nagisa and warn her that since she just transformed into a mermaid, if she doesn’t speak for an hour, she turns back into a human and her life expectancy will dramatically drop!

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Arpeggio of Blue Steel

Arpeggio of Blue Steel

It's been seventeen long years since the Fleet of Fog―a mysterious, unmanned fleet of powerful vessels that appeared out of nowhere―took control of the oceans, barring humanity from traveling between continents or islands. During those years, people the world over have dreamed of a revolt that would let them take back the seas, but there's been no hope―until now. A weapon powerful enough to damage the Fog's vessels has finally been invented, and there's just one way of getting the critical information and prototypes from Japan to America, where the weapon can produced! The submarine I-401, with its humanoid avatar―a "mental model" named Iona, who's taken the shape of a young girl―was once part of the Fleet of Fog, but has chosen to side with humanity. Now captained by Chihaya Gunzo and his crew, the I-401 is the only ship under human control that can move freely through the seas. But she answers only to her captain, and he answers to no one.

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Submarine Super 99

Submarine Super 99

In the future the world is taken over by the Ocean Empire. The Earth's only hope lies with the Super 99, a submarine designed by Dr. Juzou Oki.The story follows Susumu Oki, the chief mechanic of the SS-99 and the adventures he and the other crew members take on the SS-99 to save Earth.

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Blue Submarine No. 6

Blue Submarine No. 6

The scientist who flooded the world of the future and created a mutant species in the images of animals is looking to finish what he started, and the crew of Blue Submarine No. 6 must stop him at all costs. But first, they must try to recruit the best sub pilot that ever lived: Tetsu Hayami.

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Tide-Line Blue

Tide-Line Blue

Fourteen years ago, an environmental disaster known as the "Hammer of Eden"” devastated the planet – taking with it six billion lives, and submerging 90% of the world underwater. In the present, the remaining countries have formed a new United Nations in hopes of peace. Gould, a submarine captain, wishes to use military force to obtain this goal, while Aoi, the secretary general of the UN, believes in the power of diplomacy. In this world, Keel and Teen are twin siblings who, through a series of events, travel separately with Gould and Aoi. Together, they seek to answer the same question: is war the only way to attain peace, or can people learn to set aside their differences and negotiate?

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Pink Napoleon Fish

Pink Napoleon Fish

Chappy's only strong point is his cooking. While working at a hotel on a quiet island he meets Natsu, who shows him a whole new world in Diving. Together they search for the Pink Napoleon fish that is said to bring happiness.

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Horobishi Kemonotachi no Umi

Horobishi Kemonotachi no Umi

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Submarine 707F

Submarine 707F

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Silent Service

Silent Service

During the cold war, the Japan Maritime Self-Defense Force jointly developed a nuclear submarine with the United States Navy. On its maiden voyage, the captain of the submarine declares the submarine to be an independent state, "Yamato."

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Submarine 707

Submarine 707

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