I have to disagree with a few of the comments above. It is still debatable whether these puffers should be kept in freshwater or brackish. I kept mine in brackish for 3 years after they came from freshwater tanks at the LFS. I kept 3 dwarf puffers with 2 figure 8 puffers with no problems. Shrimp will become snacks yes! Two things you can feed them consistently, earthworms and snails, both you can grow easily at home. You could also keep a little shrimp tank which reproduce quickly and add them as they grow in numbers. The tank must stay clean for their health. Yes you do not want to try and make them puff up, it is a last resort usually results in death of the fish. They can bite you pretty badly so be careful with your hand in the tank.