Recently, we made our annual pilgrimage to the Maritime Aquarium in Norwalk, CT. I always look forward to taking pictures there. It's challenging to say the least; the lighting is terrible and most of the exhibits are in near to complete darkness, but it forces you to put the camera in manual mode and really experiment with different settings.
I refused to leave until I captured a good shot of the jellyfish - one of my favorite exhibits. I could sit there all day, watching them float gracefully around that cylindrical tank.