welcome to the madness!
So, it sounds like you are in the midst of doing some cycling. I agree with Renegade, you want to give your tank more time to cycle with nothing in it. I have a 55 gallon and what I did was seed it from another tank, meaning I got about a pint of water from another tank (make sure the tank you get it from is a healthy one. very important) add that new water to your water and that should speed up the bacteria growth in your tank. get a few guppies from the LFS
if you can't hold back on getting fish, and see how they do.