A Japanese company is working on a quirky container-like bag for live fish, suitable both for pet owners wanting to take their favorite fish on walks, and fans of super-fresh sashimi…

Known as “katsugyo bag” this portable fish tank is shaped like a long tube with a transparent middle section, a handle and a gauge, which, if I had to guess, monitors the oxygen saturation of the water. It is being developed by “Ma Corporation”, and aims to become a more elegant, efficient and environmentally-friendly alternative to the old water-filled plastic bag.

Photo: katsugyo_bag/Instagram

The katsugyo bag is currently still in development, so if it looks like something you’d happily spend money on, you’ll have to wait a bit longer. Its inventors are currently testing the device with a variety of edible fish and documenting each experiment on Instagram.

Browsing through the photos and videos of the portable fish tank uploaded to Instagram since October of last year, the quirky product has been evolving, with the oxygen gauge and feeding port (???) being added in later versions.

Improvements to the katsugyo bag are still likely to occur, as it’s tested with more types of fish. For example, developers report that fish that like to swim a lot, like mackerel, could be more problematic to transport and they promise to make the necessary adjustments to their product.

Judging by the comments posted on most of the Instagram uploads, the katsugyo bag may prove to be a commercial success, not only in Japan, but abroad as well. People are already asking about cost, how they can buy one, and generally expressing their support for the project.

Although the katsugyo bag could very well be used as a portable tank for pet fish, judging by the content posted by its creators, it is definitely aimed at sashimi fans looking to ensure that their favorite meal is as fresh as possible.