My boyfriend has a 55gal NW cichlid tank and when he tested the water about a week ago, had traces of ammonia, about .25-.5ppm, but there had been no additions to the tank or changes in feedings. So he starved the fishies for a few days, borrowed some of my filter media, and the ammonia went back to 0. After going back to his normal feeding schedule, the ammonia is back. He had rinsed off the filter sponge but that was several weeks prior to the spike.
Any ideas on what might have caused this? It would make sense if new fish had been added but there haven't been any changes in stock for over a month.
Any ideas on what might have caused this? It would make sense if new fish had been added but there haven't been any changes in stock for over a month.