I'm from Atlanta...home of the Georgia Aquarium. And as impressive as the GA Aquarium is, I actually really enjoyed Ripley's Aquarium of Canada as well.
We came here in the evening on Thursday night. It was after 8:30PM that we arrived. There wasn't a line, and while there were people here, it wasn't crowded per se. Maybe if you're interested in a less crowded experience, don't go during peak time. I'm a little surprised to read reviewer comments expressing that they wished there weren't so many people when they went...think about the economics of running any venue: they can either raise the prices and fewer people can afford to go, or they can keep it where it is and we have to recognize that there might be other people who might want to see the aquarium just as much as we do... (?) . The other comments I read that really confused me talked about how *this* aquarium is bad because it takes fishes that are endangered or otherwise sacred out of their environments and locks them up and they seem bored because it's not a natural environment....aren't other aquariums doing the exact same thing?
Not that I"m trying to defend this place. I do agree with comments that there might not be as many different kinds of fishes here as other aquariums. It is smaller than other aquariums I've been too.
At the same time, I felt the variety that they do have is pretty interesting to look at. I love watching schools of fishses swim together. And I felt the space was really well designed. The conveyor belt part was pretty amazing.
It is an interesting place. Give it a try, and be open minded about it. It's a fun way to spend an evening.