I know for rats that the Hartz mixes are nothing but junk foods. I am wanting to get this rabbit that a friend forwarded the ad to me, but the current owner is feeding him the Hartz Bonanza blend from Walmart. Is there a way I can change over his food without making him sick? I can get a pretty good pellet diet from my local feed store for less then what the Hartz diet. Should I give him mostly Timothy hay till I can complete the switch? He is already eating some hay every day. This is the pic I got of him. I hope to be picking him up tomorrow afternoon.

(Edited for spelling errors)

(Edited for spelling errors)