not adding anything but the API dechlorinator and I add it as the tank is filling. I add 5 mL for 30 gallons per the chloramine instructions. Should I try the 1 mL per 20 gal for chlorine instructions?It's odd to me you've been at this fishless cycle for this long and you're still showing all 3 components you're testing for. Generally, if you see an on scale amount of nitrate, you shouldn't see nitrite or ammonia. Again, I know water changes are a pain, but I think you have to keep at it, or add nothing to the tank and keep measuring daily.
Are you still adding things to the tank? I didn't mention it earlier, but don't add any ammonia source. Nothing but fresh, dechlorinated water at this point.