My tank has been filled (hopefully cycling), for 3 weeks now. I have a 75 gallon tank, with 7 Zebra Danios in it. I am using 2 filter systems. (Marineland Penguin 350, and Emperor 400). My readings for the first 2 weeks were really skewed due to a high Nitrite level in my tap water. So I did 2 water changes, 50% each time with better water and that helped immensely. So for the last week my water readings, using the API freshwater test kit, have been 1.0 ammonia level (that is also the reading that my tap water reads from the faucet), Nitrite level is 0, and Nitrate level is also 0. So does that mean after 3 weeks my tank has not even begun to start the Nitrogen cycle? Please help. Thanks