A 10 gal aquarium should be fine for a hatchling ball python. If he's not eating, it means something is making him uncomfortable. Make sure that your hotspot is around 88-92* (I keep mine at around 91*) and your ambient temp is in the 80s (mine is usually 81*). If your temps check out fine, then look at your hides. You want two snug hides that look the same! Sometimes they will choose their favorite hide over choosing the right temperature for them. If your hides are fine, look at your tank floor. Since a 10 gal might be a bit scary for a baby, clutter it with fake plants, crumbled up paper, additional hides, etc. You want to make sure they they can get form one hide to the next with some cover. If your tank flood is cluttered, it might be helpful to change the way you're feeding the ball python. Like someone else said, they will rarely just eat a dead mouse that you throw in. They are a predatory/species. Make sure the mouse/rat (ideally you want them to be on rats...but if mice is all you can find, there's fine until the snake gets bigger) is completely thawed. Then, instead of dropping it directly into the tank, grab a pair of tongs and grip he mouse/rat (for a hatching, you want a mouse hopper or rat fuzzy ideally) by the scruff of the neck. Then lower it to the tank floor and wiggle it (we call it a "zombie dance" on here). Your snake will smell it and see the movement and then strike it, coil it, and then eat it. Another thing to note, ball pythons do have a tendency to go off their food. I wouldn't stress too much over a hatchling not eating for one or two weeks for you.