Look up the water report for your area. If they use chloramine then you will get an ammonia reading from the test. It will also not evaporate out of the tank like chlorine does, which will cause your tank to not cycle. You should be dosing with pure ammonia, if you don't have fish in the tank. Take it up to 4ppm and wait for it to drop. If you have fish, then it's hard to tell what's going on if there's also chloramine. I'm sure someone can help you a bit better than I can, but this should be a decent start.