I was wondering that as well initially, but if his test kit is accurate and he's running the test coreectly, it's pretty unlikely that he's zero for ammonia and nitrites and also showing a 10 ppm reading for nitrates unless the tank has been cycled.Did you cycle the tank before you got the betta? Have you tested for nitrite?
Is he pooping at all, and if so, what color is it? I'm starting to wonder if it's an internal infection or a bowel blockage.
WYite