Join Date: May 2008
Location: San Francisco, CA
Tap water shouldn't contain ammonia or nitrate to begin with. Or else water changes would be pointless.
The point of having a time period of no livestock is because the tank needs to cycle. In order to cycle, you need some kind of ammonia source to start it all up. If the tank was just sitting with nothing in there, then it probably didn't really start any sort of cycle. You may want to check your water parameters before you start adding stuff.