HI all,
I didnt have the test kit for nitrites but I did test for ammonia, nitrates and pH.
Nitrates were 0
Ammonia was just about .25ppm (slightly green)
pH was acidic.

Seems that you were all correct and the water quality is horrible. I had no idea that such a small frog could make the water change so fast and thought that the weekly change was ok. I am going to upgrade his conditions as soon as I understand if my tank is clean enough or if I need to do a better cleaning job first.
I used basic soap, kind of like antibacterial hand soap with very hot water to clean last night. Scrubbed soap all over and rinsed. Repeated one time.

Thoughts?