I hope you don't my I add few small points.
Generally, to avoid seeing your branded camera on the fish tank, try to keep the ambient as dark as possible. Cover any lights leaks from your fish tank above water level of the tank.
Use lens hood if you need to shoot with flash and DO NOT shoot perpendicular to the tank unless you are very very near (lense touching the tank already... lol).
For those with smaller tanks and can afford a few more strobes, add strobes on top and sides of your tank. I got a friend who use up to 8 strobes shooting a 1 feet tank (IIRC) and he usually shoot at above f8 for his macro pictures. This ensures he the picture superbly crisp and sharp and best of all, the whole fish in focus. I was told he used up to f16 sometime.