I am very new to this hobby, but here is my experience with them:
I would not recommend them for a community tank... mine are little bullies and nip on everything that is in the tank with them... I had to set up a species only tank for them, because they started to bother my other fish in the community set up...
Other than that:
- They stay small (about 1-1.5 inches).
- They like live and frozen food (mine totally ignore freeze dried food), and snails.
- Since they are scale less fish, they are sensitive to medication.
-They need fresh water tanks, not brackish.
- They need a lot of hiding spaces and broken lines of sight, because they can bully each other if not provided
- You need at least 2-3 G per dwarf puffer to avoid trouble.
- Some are OK with Otocinclus catfish (mine are not) or ghost shrimp (mine leave those alone).
I hope someone with more experience will either agree or disagree with what I said... as I said, I am very new to keeping fish. But I hope I got things right and could help a bit.