Blue Submarine No. 6 - Recommendations

Alt title: Ao no 6-gou

Blue Submarine No. 6

If you're looking for manga similar to Blue Submarine No. 6, you might like these titles.

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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Aldnoah.Zero

Aldnoah.Zero

Years after a great war was waged between the portion of humanity that migrated to Mars and those who chose to remain on Earth, a tentative peace has been struck. But not everyone is happy with the status quo. When the Princess Asseylum of Mars makes a diplomatic visit to Earth in an effort to strengthen ties, some see it as an opportunity to reignite the flames of war. Can the citizens of Earth stand against the awesome might of the Martian Kataphrakts a second time?

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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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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 707

Submarine 707

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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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Mobile Suit Gundam Unicorn (Light Novel)

Mobile Suit Gundam Unicorn (Light Novel)

Universal Century 0096. Three years after the last conflict between Neo Zeon and the Earth Federation Forces, the tentative peace of the Earth Sphere is about to be shattered again. Cardeas Vist, the head of the powerful Vist Foundation, has decided to hand over "Laplace's Box," the secret of the Foundation's prosperity, to the supposed enemy, Neo Zeon. Banagher Links, a student at the space colony Industrial 7, rescues a mysterious girl who calls herself Audrey Burne. Audrey is seeking to prevent a war, but it seems she has come too late. As Banagher's home colony is devastated by the attacks of the enemy mobile suit Kshatriya, he finds his strange destiny and is forced to fight in the formidable weapon system known as the Unicorn Gundam.

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Gunparade March

Gunparade March

In 1945, at the close of the Pacific War, an invasion beset the planet Earth. Droves of Phantom Beasts - aliens from another world - landed and waged war against man. Humanity was forced to unite and fight this common threat, but years later, in present times, the death toll has depleted the military forces, leaving Japan with no choice: They must enlist the help of teenagers. Atsushi Hayami is among those who, rather than lead a normal high-school life, must take up arms to ensure the survival of mankind.

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