I went to the Art Aquarium in summer 2014 and it was a truly fantastic experience. After seeing more than 5,000 goldfish in different tanks, with a myriad of lights and surrounded by soothing music, I also purchased some souvenirs at the gift shop right outside the exit. It's worth seeing and enjoying, just keep in mind there are usually a lot of people in the evenings and on weekends. Great place to visit for couples or families, too. Tickets are around ¥1,000.
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