The stickies at the top of this page will be your starting point. Also, I would google or search this sub forum for particular settings. Where you start from is also based on your experience level... if you are new to DSLRs completely, a lot of what you will want/need to learn will go beyond the specifics of aquarium photography. The main pointers in regards to aquarium shooting is learning to WB your camera properly, shoot straight through the glass to minimize distortion, leave all other lights outside the aquarium off to prevent glare off the aquarium glass, and for coral shots use a tripod. Start shooting away and posting and then everyone will be able to chime in and help you out