when did you get your tank.. It sounds like you are failry new to the hobby. Before spending a lot of extra money in the hoby, i would recommend doing some research. You will be able to find everything you need on this website.
I would recommend that if your tank has not already cycled, you put your sand and rock into your main tank to help with the cycle. It will be worse for your system if you add these things over time. After your rock, water and sand are in the tank a cycle should begin shortly after, if you don't see it begin you can use a piece of raw shrimp as stated earlier.
It is good to see you are excited about beginning in the hobby. I am sure you will have a fantastic tank before too long, but you need to let it develop... unfortunatley this will take some time.
As i said before, reasearch is the key in this hobby, research and time!