You're correct. But keep in mind, API test kits are not very accurate and most of the times you will still see some green tint in the results for ammonia.
From a full tank picture + stated timeframe as to how long your rocks have been underwater we can state the ammonia off the pics, not the test ~ lets see what cha got / details too
This is the problem I have with all of the guess the color kits. My eyes just don't pick up the colors like others. Why I rarely test if it's not a Hanna checker.