They easily break, you can break them into any size you like. I just started giving about an inch a day as a treat, and then increased it and reduced the other pellets accordingly till they were on the same weight of fibafirst as they had been of excel. I ended up changing though, because my bun has daily medication and its harder to put it on fibafirst than a bowl of pellets, so my buns were only on them for a few months.