I renewed my aquarium membership today for a year. YAY!
To answer a couple questions, no polarizer was used because I don't have one for this lens (though I really need to pick one up). This is no flash, and the tones are exactly waht you see when you go there. It's very dark in this area, I think the dramatic lighting in the tanks combined with the darkness is what makes it come out to the right shade (without a cast).