Yesterday I did a 50% water change. Before doing it i tested and ammonia was at 0 along with nitrites at 0. I did it my usual way, 50% taken out of my 90 gallon tank and refilled with buckets. What i did was add a capfull of prime to the first bucket of tap water and that was it. The rest of the buckets had no prime added. Today, around 12 hours after, I test the water and my ammonia was at 0.5 ppm and nitrite at 0.25 ppm. What could've caused this? Did i uncycle my tank or is the prime in the water and somehow messing with the API liquid test kit? I tested the tap and ammonia and nitrites are 0.
