How to take pictures in?

My family is going to SeaWorld next weekend, and I know they have a lot of dark aquariums there. I was curious as to the best way to take pictures inside of them. I know flash could be good, but it's hard to make it not show up in the pictures. Any help would be appreciated!

If it makes a difference, I use a Nikon D40.

Use as low an aperture as possible, to let in as much light as possible. Also, If that isn't enough, and you set your cameras shutterspeed as low as possible without having shaky photos, don't be afraid to up the ISO, a little noise is better than a blurry, shaky photo.

Just a personal opinion.

It's difficult in low light situations. You'll have to set your ISO way up, probably to 400 or 800. Your pictures will be grainy, but it's better than having a blurring photo.

In low light, try to set you camera down somewhere and shoot. A tripod would work but it's too bulky. Another way to steady yourself and the camera is to use other objects to stabilize yourself. Leaning on walls or sitting on chairs/benches works great. It's still difficult, but anything you can do to stabilize yourself will help.

Hope that helps,
-Wei
www.artofwei.com

Here's agreat article just given to me on that very subject: http://blog.gregdisch.com/2009/07/26/how-to-photograph-a-public-aquarium/