As part of driving across the southern states back to CA, we were in Phoenix for 14 hours.
Due to a lot of time in national parks, and adding Organ Pipe Cactus NP to the itinerary, we only had half a day in Phoenix. We arrived pretty late the first day, just in time to spend a quick hour at Odysea Aquarium, which was somewhat out of town.
In the end, the aquarium isn't huge, so 1H was enough. It's not one of the best aquariums I've seen, but it was still decent: