I am week 5 into a fish in cycle. A little over a week ago I added some hornwort to the tank, and now my ammonia is 0, nitrites are 0, and nirtrates are 0. Previously, I was getting .25 ammonia, up to 5ppm of Nitrite and the highest I ever had of Nitrates were 5 ppm. I know the plants help process ammonia, nitrite and use nitrate....but is this inhibiting my cycle? Is my tank cycled? I've had 0 readings for 3 days in a row now...