Fridays and Saturdays are the busiest days by far.
Even on a "busy day" I never feel overwhelmed by crowds. It's very spacious.
The aquarium is least busy when it first opens each morning. By midday, the aquarium is busy, every day.
It's busy every day. My husband and I don't like crowds but we weren't bothered by how busy it was, to exciting to be concerned about to many people (kids). We really enjoyed our time there.
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