i have been doing a fishless cycle in my 56 for about a week, i traded the new filter cartridge from the new filter with one of the used ones (have four) in my 55. have been adding the ammonia every night and 2 days ago i got my nitrite spike and halved the amount i am adding. checked last night and i have nitrite 5 and nitrate 20, but still have ammonia 2-3. should i start adding even less ammonia? thought it was supposed to 0 out when the nitrite spikes. i am so confused