SethC...please tell me you cycled the tank first?? Puffers are VERY sensitive to water parameters and putting them in a tank that hasn't been cycled will probably kill it. Please read on this forum about fishless cycling....please return her to the store until you cycle your tank. I have two dwarf puffers (each in their own 10g tank). They can be in a 5, but prefer bigger space. Anyway...I feed mine frozen blood worms and snails. They have to have a regular supply of snails as food. Please private message me if you have any questions. If you decide to keep her and try to cycle the tank with her in it, you will need to do about 50% water changes daily until the tank is cycled (roughly 4 weeks) in order to keep her healthy and alive.