How big is your tank and how much ammonia are you adding?
Tank is a 32G.
The ammonia I got is 5% pure ammonia (supposedly). I add enough on a daily basis to keep the levels at 5ppm. I am using the API test kit for ammonia. In my case, with a 32G, 10 ml of 5% ammonia got me the 5ppm levels I was looking for.