I have the same camera, but I guess we're not local to each other. Check with Raf or Diana though, I think they shoot with that model as well and they'd be closer.
Tank photography is tricky - I used to think I was OK at photography until I started trying to shoot my tanks. Now I realize I'm horrible at it. Anything non tank related seems to go well though. I guess the lighting really throws things off.
A lot depends on what glass you're using too. What lens are you using? If not doing so already you should probably consider shooting with a macro lens and not bother with anything else.
When I was shooting with my 35mm I had a 90mm macro lens and it worked out well. Moving to a DSLR body though puts a 1.5x magnifier on your focal lens so it became the equivalent of a 135mm. Which is great if you want a photo of maybe nostril on a snail but not so good if you want a picture of a whole animal. I found I had to step so far back from the tank to fit a fish it kind of defeated the purpose of a macro lens.
After reading this thread,
http://www.canreef.com/vbulletin/sho...d.php?t=36153&
.. I started saving up for the F2.8 60mm Macro lens. Found a good deal on ebay. I have to say, this is a great lens. It's more or less the standard micro (Nikon's term for macro) lens that Nikon offers nowadays. Highly recommend looking into this lens (if you're not using it already that is
).
Lastly, practise is underrated
Seriously, I find I'll shoot some 90-100 pictures in a sitting and keep maybe about 4.
I guess I need those tips too, but in the meantime, shoot lots and vary it up and see what works well.
Anyhow good luck, hope some of this helps.