Do you have the tank already? If not I would recommend a 75g instead. The front to back dimensions of a 55 is 12" where a 75 is 18" that extra 6" makes a world of difference when setting up your rock scape. For the lighting it all depends on what your planning to do but for the cost of it all get LEDs, you will need either a 4 foot fixture or 2 pendant style fixtures. Taotronics LEDs have gotten great reviews and you can get them cheap. I spent $700 on a 6 bulb t5ho fixture for my 55 and you can get the LEDs for about $300. LEDs are easier on the power bill, don't need bulb replacement every 9 months and if you get the proper ones can support anything you want to put in the tank.