If possible boi I would be running the new filter on the old tank to cycle it that way, or use half the filter media in the old filter in the new one. I would also use half the water from the exisiting tank in the new one. Although there is not much of the good bacteria in the water itself, it will be the pH, temp etc the fish are used to.
Once the fish are moved from the old tank, will it still have fish in it or will it be empty? If empty, just shift the whole filter unit to the new tank (if possible) and then it is already cycled.