Bad smell is bad. You have to get the system properly cycled before you add valuable live stock. 2 ppm is lethal, and measurable level is harmful over time.

I like the turtle method to cycle a new system. A few large turtles add a good bio load to get a cycle going and turtles are not harmed by the ammonia. Once the system is cycled and stable the turtles come out and the fish go in.