Help with using/reading Seachem Ammonia badge

[blackstallion]

This is my first time using the badge. It's in my QT with 1 fish and has been up and running for about a week. Right now it looks like a solid yellow, BUT, the edges of the circle have a green outline. From the groups experience, does the badge start changing color uniformly OR does it start from the edges OR center?

I'm running a HOB filter with bio media that I seeded with Bio Spira Live bacteria about a week ago when I started the tank. I haven't performed a WC yet.

Right now I'm dosing copper so I can't verify the Ammonia level with a test kit.

 

[Billldg]

I have only seen it change uniformly personally.