Setting Up a New Tank; Nitrites Off The Scale

So, I have a nuvo fusion 20 gallon that I'm trying to cycle. I started it up with 20lbs of caribsea live sand, about 15lbs dry base rock, and a small bottle of biospira. It has been up for 6 days now and if I remember correctly My ammonia hit 0 on day 3. My question is if it is normal/detrimental to the cycling for my nitrites to be maxed out after the ammonia has gone down. I have done two 30% water changes and even a 90% change to try to lower them as it is my understanding that high nitrites can slow or stall the process. All water changes were done with tap water conditioned with prime. And I have tested water at the tap for everything and it all comes back 0. Testing was done with API saltwater master kit. Any incite would be much appreciated. Thanks!