Nitrates in uncycled tank
I just put water in a used tank. Haven't added fish or ammonia, just declorinator. I have washed the gravel and am reusing it. Tested the water today and there are nitrates in it, but no ammonia or nitrites. I tested the tap water and it is 0 across the board. What could be causing this? How will it affect my cycle, as there is no possible way it could be done yet. Only had water in for a couple days and never added ammonia. I'm using the API liquid test kit as recommended. Any input is appreciated!