ammonia reading after water change
I tested my water before water change this morning and I was at 0 for ammonia, nitrite and nitrate.
Changed approx. 15% of the water with tap water that laid in the container for 7days and treated with Prime.
This evening, i tested again the water and I get an ammonia reading of 0.25
How is that possible? Tested tap water and it is at 0.
I did not vaccuum or touched the filter. Only removed water.