It is possible to "Jump start" the cycle process with the addition of used viable filter media from existing tanks. Gravel, water, rocks, whole filters, filter media and even decorations can be used to do this. The beneficial bacteria colonizes the surfaces of the tank. While most is found on the glass surface there is some to be found on the surfaces of the things mentioned. These will not cycle your tank over night but it will help the process along by introducing the various bacteria to the tank earlier thus giving it time to take a hold and speed the process along