Tokyo aquarium still baffled by mystery fish deaths


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Well, as a long time aquarist the only things that come to mind are overfeeding and insufficent weekly partial water changes. Also, is the heater working?

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Must be one fat Tuna by now. Survival of the fittest in full display. Reminds me of Battle Royal.

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I went to the aquarium in Nagoya with my J-wife and she said it was like going to a ranch and looking at cattle before they butcher them for steaks.

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Have they tested the Nitrate levels in the water and contamination of their filtration System

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I wonder, did they change the water recently and use some from around Fukushima?

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It looks like he won the Fish Battle Royale. It's time to set him free.

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Anything related to this? Anyone speaking Japanese can inform the Aquarium?

Mass fish deaths off Singapore coast spark concern

The environmental authorities said the deaths were due to a plankton bloom, where a species of plankton multiplies rapidly, damaging the gills of fish. It can be triggered by sudden changes in temperature, high nutrient levels in the water, and poor water circulation.

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FightingViking, that fish should NEVER be returned to the ocean, why well if the mysterious deaths of the fish is put down to a virus,that fish could well be a carrier of the virus, thus infecting the rest of them, and you could end up with millions of dead fish, and then the question would be, can that virus be transmuted to humans? so there would be a ban on eating these fish until it has been cleared for human consumption.

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Not actually the first problem with tuna in aquariums. Many years ago there was a problem with tuna at another aquarium becoming overly stressed both my the people (you can see in and they can see out) and the great variety of fish swimming in a small tank. Fish tend to congregate in schools made up of the same species. Moreover, individual fish in the schools swim at the same pace as the other fish in the school. Putting too many species in close proximity to each other results in confusion because the fish cannot regulate the speed at which they swim. I seem to remember that at the other aquarium the tuna started to become deformed by growths around their heads. A specialist in aquaculture told me that this was the result of stress.

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Easy answer that should be obvious to all - they are wild creatures held in captivity.

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"We suspect that it could be due to new factors that were not present before."

This guy SURELY must be a professor and a genius.

Close the aquarium down until you figure it out. That might get the vested interests working faster.

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Confining so many large fish in such a TINY areas is very HIGHLY conducive to spreading disease, surprised it took this long.

As for the last one, best not to release as its likely sick as well

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Have they looked into the possibility of a mole from Sushi Zanmai?

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Poor Charlie.

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its simple, they are demoloshing Rinkai Koen for Olympics, so there is no way they will move this Sea Life somewhere else as it's not really making so much money, so the best way to handle it is to Kill the fishes and make it look like they died on Natural causes. So they can demolish Sea life easily.

It's too obvios, Sea Life has been there for a long time without any issues, then suddenly after announcing that Rinkai Koen will be demolished for Olympics the fishes started dying? hmmm indeed this is fishy....

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FV: As for the last Tuna - why not let him go back to the ocean ?

If he's the 'Typhoid Mary' of the tuna world, there might not be any left next year if they do that.

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We suspect that it could be due to new factors that were not present before.

Check for radiation? #ignoredfact

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We suspect that it could be due to new factors that were not present before.

Ya' think?

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Having said that i do find a trip to the aquarium soothing.

Aquariums are indeed very soothing but you don't have to "go to one"... I have a beautiful aquarium screen saver on my computer(s)... I also have a "home-aquarium" - but that takes quite a lot of "looking after"... ;-)

just one lonely tuna roaming

As for the last Tuna - why not let him go back to the ocean ?

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Aren't they demolishing RINKAI KOEN soon for Olympics??? Maybe that will solve the "MYSTERY"

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How much do we know about diseases in fish? all it takes is a single unknown pathogen introduced to the aquarium to have everybody scratching their heads. We keep finding every year new viruses that produce lethal disease in humans even after decades of searching, it is not surprising that we could find many more if we do the same on other animals.

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Poor lonely tuna. must be some mystery virus or the sadness of having to swim round and round in a tank rather than free in the ocean. Having said that i do find a trip to the aquarium soothing.

-2 ( +1 / -3 )

The whole thing sounds fishy to me.

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