My tank is a 110 litre that has been set up for 1 week. I has 2 zebra danios, 5 lemon tetras and lot of dwarf sag, hygro and ludwiga repens. It has some filter media form my old tank to help cycle and has had 2 40% or so waterchanges in that time. I have been testing the the nitrite and ammonia daily and from the start it never had any ammonia and the nitrite has never got above 0.5. What does this mean and how long do you think it will take to cycle?