I'm new to fish too, so I don't know much, but I can tell you my experience with a Bio-Spira assisted fishless cycle. I was cycling a new 15 gallon for my son. I put in the Bio-Spira and started dosing with ammonia. The ammonia eating bacteria showed up pronto, the tank was clearing the 5ppm of ammonia a day within five days. BUT, the nitrites stayed really high for three weeks and weren't budging. I think the high ammonia might have killed the nitrite eating bacteria from the Bio-Spira.
After three weeks of waiting, I changed out 80% three times in a row until nitrites were at 0. I re-dosed with Bio-Spira while ammonia and nitrites were both at 0, waited 12 hours and then started re-dosing with ammonia. But, this time, I split the ammonia dose in half...half in the morning and half in the evening. I was hoping that, this way, the ammonia would never be high enough to kill the nitrite eaters. The tank finished cycling four days after that. We added fish after another three days and ammonia and nitrite have stayed at 0 for three weeks now, so I'm confident that the cycle was really and truly done.
