Do really high nitrite levels inhibit growth? I never changed mine and I'm sure they were much much higher than that (test only goes to 5). My cycle ended in less than a month. I guess my reasoning was "more food for the bacteria to eat, therefore more bacteria will grow". I dropped from 5ppm nitrite to 0.25 ppm
nitrite in 1 day (about 25 days into the cycle). I had a Nitrite consuming machine on my hands.