Yes, DJ is right, you are in a "fish-in cycling situation" and that's written about in our "Beginners Resource Center" at the top of the "New to the Hobby" forum here.
You -do- need to do significant water changes until you can get a proper test kit. You also need to use good water change technique when doing these. You use tap water (not distilled water ever, although we'll also want you to post up your tap water stats right away when you get your kit) and you'll need to add "conditioner" (a liquid chemical product from the local fish store that removes chlorine and/or chloramines which are harmful to both fish and the bacteria we need you to grow in your new filter.) You also need to roughly temperature match (your hand is good enough) this conditioned water before it goes into the tank. Since you're in New Jersey (USA) you probably have a typical hot water tank that's fiberglass lined inside and so using a mix of hot and cold from the tap to do the temperature matching should be fine.
The test kit is important. Many of us like and use the API Freshwater Master Test Kit. It has tests for ammonia, nitrite(NO2), pH and nitrate(NO3). The ammonia and nitrite(NO2) are the really important toxic things we have to worry about for the health of the fish.
Its also going to be important for you to work out the right types of media (sponges, floss, etc. in filter) early on so that you will have a good home in your filter for the correct two species of bacteria to grow to become your "biofilter!" Carbon is not the ideal material for a good biofilter. Its correct use is as a "chemical" media for removing medications, removing yellow tannins from bogwood and occasional things like that. It shouldn't be in the filter on an ongoing basis usually, because the way its properly used is to remove it every 3 days, which is how quickly it fills up with meds etc.
~~waterdrop~~
