What I meant was that a "macro lens" is specifically designed to get a 1:1 ratio and to get very close to the subject (in this case the corals) with a very small number on the minimum focus distance. What I'm pretty much saying to you is,, you probably don't need a "Macro lens" for what you're looking to do. Nothing wrong with the macro lens, but you probably don't need to spend so much for the extra feature that you don't need, which is macro capabilities.
I'm not very familiar with third party brands such as Tamron or Tokina (I'm sure they're fine) but if you wanted to stick with the dedicated Nikon lenses, and for what you want to do and your budget, I would suggest the 50mm 1.8G which you can pick up brand new for under $200 (I think). If you were willing to spend a bit more, which is around the $400 area,, you can pick up the 50mm 1.4G which is a better made lens. Whatever you decide to go with, if you're looking to buy Nikon, just make sure you stick with the G or E type of lenses. Don't buy the "D" lenses,, they don't work well with the digital cameras and the AF won't work at all.
