alyssia, test kit is new, tank is about 6 months old now, everything has been fine for about a month since I got everything streightened out with the salinity, I used to have nitrates in there and low salinity, ammonia and nitrite were always good. Till now, I am not sure what is causing it. I have been speaking with Lion about this problem. He thinks the ammonia spiked but I have enough bacteria to bring it back down quickly, but not enough to bring down the nitrites. I did a water change today, 12 gallons out of a 55 that I never keep filled to the top So probably about 45-50 gallons in there, it's about 3 inches from the bottom rim of the top of the tank. Anyway, the nitrite didn't go down. I added Stress zyme and more Amquel plus to help. I have no clue what is causing these spikes without the presence of ammonia. What do you think?