Hi everyone, I am new to the saltwater world and am confused about my cycle. I have a 75g tank filled with 50 pounds of regular rock from reef cleaners and 35 pounds of cured live rock from my LFS. I have had the tank together for little over a week now. I introduced two medium raw shrimp on the first day in a mesh bag to get the cycle going. I have not been turning on any lights and have had my protein skimmer running since day one. It is pulling plenty of dark, smelly stuff from it. I have been testing my levels ph, ammonia, nitrite, and nitrate, and salinity levels from day 1. So far I only received a small ammonia spike to about 0.5ppm, nitrite to 1ppm and nitrate to 20ppm. Salinity is in between 1.023-1.024, ph is 8.0. Temp at 79 degrees. Well yesterday I tested my water and it seemed like ammonia was down to 0 (so hard to tell the ammonia on the API color chart for me but it was the lightest it has ever been), nitrite was clearly 0 and nitrate was 40ppm. Today though it seems like the ammonia went back up to 0.5ppm (darker today) and nitrite is still 0 and nitrate is still 40. I am confused. I know little over a week is not enough time for the cycle to finish but why would everything seem to be progressing and all of a sudden it seems to have restarted. Should I remove the shrimp? Should I do a water change? I'm just confused and have learned so much from this forum already. Thank you all!