Just to answer the couple of questions:
The Lightsea torch has an intense blue light produced from an LED but also through a filter on the torch. A Tiffen yellow filter on the camera lens makes the coral fluorescence stand out.
As part of the Nightsea package you get a special pair of glasses which emulate the tiffen yellow filter so you can actually visualise the shot befor bringing the camera anywhere near the tank. Pretty cool.
I'm using a Canon 1D MkIII with a Canon 180mm f3.5 L Macro lens, tripod and cable release.
The iso is set to 2500 and its a 2 second exposure.