We also hit the aquarium the other day. Osaka has a world famous one that spirals down. They have some unique fish and mammals like the giant whale shark and a sunfish :) Here are some pics.
Outside the aquarium. They always decorate around this time of year for the holidays. There is also a huge ass ferris wheel called Tempozan that gives you a great view of the whole city.
I love the aquarium. So many cute fishes and animals.