Depending on what kind of camera you have, like stated above, a high ISO helps. I was told once when I was visiting our National Aquarium by a tour guide if you press your lens to the glass you eliminate glare. I use that technique sometimes when I'm photographing my own fish. It works, not always, but it helps. Having a well lit tank helps also.
I have 2 cameras I use to photograph my fish. [had 3 but my G10 got thrown into one of my tanks by my daughter
]
1. Canon Rebel Xti settings I use
[I shot mainly in P-Mode]
Photo examples
2. Canon PowerShot SD790
[I would assume most point and shot [canon] cameras come with an "aquarium" shooting mode. I use it when using this camera to photograph my fish.]
Photo example
I have 2 cameras I use to photograph my fish. [had 3 but my G10 got thrown into one of my tanks by my daughter
1. Canon Rebel Xti settings I use
[I shot mainly in P-Mode]
Photo examples
2. Canon PowerShot SD790
[I would assume most point and shot [canon] cameras come with an "aquarium" shooting mode. I use it when using this camera to photograph my fish.]
Photo example