Pet mice are small and don't eat much, usually between 0.1 and 0.2 ounces of food each day. They don't overeat pellets and will stop when they're full, but they do prioritize more interesting fresh foods. Therefore, it's important that you not feed so much fresh food that your mice won't touch their pellets, since these contain a well-balanced range of nutrients that’s difficult to replicate with fresh food unless you're an expert in mouse nutrition.