It depends on the weight. 3-6 would probably be average. I think the most commonly used number is about 5. But yeah, it depends on the weight of the hedgie. If they're smaller, they can have more; if they're getting pudgy, less. I would say 10 is a lot and you might want to cut it down a bit. They should also have a wheel (I hope they do but I don't know so I thought I'd mention it), especially if you're feeding that many mealies to them since they're a really fattening treat.