I have a fuji finepix s5000 as well. Kicks butt, both the photo instructors at the
CC where i work were impressed with it when I got it last year at $325.
As for tips:
Use a flash, but don't shoot dead on. Angle your shot so you don't get just a flash reflection.
Turn off all the lights in the room and use a light directly above the tank.
Use something to steady either your hands/arms or the camera.
Either use the macro setting or sit back a bit and zoom in if you have optical zoom ( praise the 10x on the s5000!).
Take lots of pics. Out of 30 or 40 I take at once, I get 3 or 4 keepers (in focus and I can recognize what it is), of which maybe 1% are truly great.
Some digital cams have a feature where they will take several pictures with each push of the button. Works great for high-motion shots, usually one of the group is right on.
If you aren't interested in printing large pics, try taking some video and just grabbing a frame out of it. Works great for pictures destined to only be viewed on a monitor or TV.
Here's a pic of the only fish I've named, a Columbian shark I was lied to about by a
lfs (which is why I bought it). I named him Immelman from his weird behaviour of doing an Immelman turn and crusing around the top of the tank as if it were the bottom. Pic was taken from below looking up to the underside of the surface.
