Figure 8 puffers

They need 10 gallons each by themselves. They aren't a recommended community fish since their temperments vary from each puffer, so this puffer might be docile, and this one might be vicious, etc.

They are also a BRACKISH fish, meaning no freshwater fish in the tank. Needs SG of 1.005-1.008

Ditto on everything that Oddball said. I have one in his own 10 gallon and he is not very friendly. Anything that goes into the tank is edible in his book.
I hand feed him snails so he is smart enoough to not bite the fingers that feed him.

I will warn you though. They are messy eaters and I have never been able to get mine to eat pellets. He lives on frozen blood worms, snails (luckily my local petsmart lets me come by weekly and pluck snails for free), and live ghost shrimp. You also need to be the algae maintenance for them. There are not alot (actually none that I know of) of brackish algae eaters so you need to do quite a bit of maintenance to control algae.

But I will also say that P-diddy has a great little personality and I love to watch him hunt ghost shrimp and snails and just flutter around his tank.

They WON'T eat pellets or flakes. There ARE brackish algae eaters, but grow to like 2-3 feet and are NOT aquarium fish.

PM me some questions and I can answer them.