If you're looking for a relaxing aquarium visit, we suggest going about an hour before the aquarium closes. At this time there are only a few people left either strolling around or watching sharks swish by in the "Chain Of Life - Water's Blessing Tokyo Tank".
While lounge music plays, you can enjoy the variety of sea creatures at your own pace without feeling bombarded by a crowd of people. One of our favorite tanks houses Garden Eels. They are both photogenic and entertaining.
For those uninterested in sea snakes, you can also see fish typical to Japan's waters as well as visit what we labeled "Jellyfish Alley". Like most aquariums, this one forms one big circle where you can flow uninterrupted from one area to the next. Whether you walk up the ramps or down, there is always something to see.
At the center of this aquarium is an open-air tank that features one of nature's miracles, flightless in air, fluid in water: The penguin. 8:00PM seemed to be their bedtime, but there was definitely a few rascals in the bunch. The railing between you and the tank is barely an arm's distance, so it really makes you feel like you can touch these tuxedo-ed sea chickens. At the rear of their habitat are fur seals, which you can observe from above or below.
When we visited last June, there was a goldfish exhibition going on for the summer festival/yukata-wearing season. It was a beautiful display of all kinds of goldfish. One thing we noticed is that all of the tanks were immaculate. The staff does a very good job keeping not only the tanks, but also the facilities very clean.
We loved the Sumida Aquarium mostly because its size isn't overwhelming and if you go at the right time, it's not very crowded. The inside felt more like an art exhibit than an ocean world, so if you like that kind of thing, we definitely recommend checking it out. If you're in Japan for an extended period of time and you're thinking of visiting the aquarium multiple times, we recommend buying the yearly pass. More than two trips makes it worth it and this aquarium is definitely a sight to see more than once.
Address: TOKYO Solamachi, 一丁目-1番-2号 Oshiage, Sumida, Tokyo 131-0045, Japan