Water testing and partial water changes ?

Have u used water conditor and cycle chemicals? fishes can't live with tap water and allow tank to be cycling for couple of weeks or did u use water from previous tank?. No ammonia or Nitrite that strange because water sounds healthly for fish. Have u use "high range" test?. Sounds like ur tap water needs to treat before do water changings, but u haven't mention how much water u have change, do 15% water changes with treatment in weekly, Never do more than 30% water changes, it could cause fish stress. I see that u have used tap safe and stress coat those are fine.. maybe amout dosage, u can check what it says on bottle, if still not sure, visit petshop and ask