overnight my nitrites dropped from 2ppm to about .75ppm. does this sound like the cycle is ending? also, I had been seeing nitrates at about 40ppm, and added some tetra conditioner wwith nitraban, which is supposed to get rid of nitrates. I just checked my water and the nitrates are reading at 10ppm. Is this ok, as long as my ammonia and nitrites are at 0? should I sotp adding this?