If you heavily planted the tank from the beginning, literally covering the substrate with plants or floating a lot of plants, they will be consuming ammonia as soon as it begins to appear and no nitrites will be formed. With the amount of light you have you really need to be sure you have plenty of CO2 from the beginning too, along with the other ferts. If there are no fish in the tank, why not just jack up the CO2 bubble rate a lot until the plants get growing very well? Instead of a bubble counter just stick the end of the CO2 tube in the water and you can see how much you are flowing. Then reconnect it and recheck it that way every day. I would also limit the lighting duration to less than 10 hours a day.