Tank Photography

Hi,

Just got my first digital camera. A Canon Powershot A70. I have no
experience in photography, but am enjoying learning about my new toy.

One of the first things I've found is shooting pics of moving fish in
idiosyncratic tank lighting is a bit tricky. :-)

So all of you with those great pics posted online, any tips or suggestions
for a newbie? As far as Fstop, shutterspeed, use of flash, ISO settings,
anything else.

Now if you'll excuse me, I have to go replace my batteries yet again :-)

TIA
Phil