Generally 3 hours. ;)
The aquarium has both indoor and outdoor features so you could spend many hours there - particularly if you enjoy watching the polar bears being fed and the walruses with their babies swimming in the pool. There are a number of "touching" experiences. It would depend on the ages of the visitors and their attention span!!
I would plan for half a day at least. The indoor tanks can be viewed in 1-2 hours, then the outdoor animals can captivate you for a long time!
The time you want! Last March I went with my grandchildren and we were there for all day, 9 30 to 15 h 30, there is a lot to see, children want to see all the show with animal... you have a lot to see inside too!
It depends on what you want to do; if you read every information board throughout the park, it can stretch to a full day but if you browse through the park, see the seal show, read the boards that most interest you, its a good half day attraction.
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