It sounds like your tank hasn't gone through the ammonia cycle yet. I would follow the advice given here, go get a piece of raw shrimp from your grocery store and throw it in the tank. You will then need to test every day for ammonia, nitrite and nitrate. If your ammonia test never goes over .25, its probably because its an API liquid test and its gone bad, which is a common problem. Either pick up a second kit, or have your LFS verify the results of your test.