The dwarf Indian Pea Puffer is a cute little puffer fish from India. It is a strictly freshwater fish originally from the Pamba river. These little guys can be a bit aggressive, so it's best to only have one male per tank, or to have quite a large tank where males can set up their own "areas."
These little guys grow to a maximum size of 1/2 to 1 1/2 inches. Even so, they have been known to nip at the fins of bigger fish in their tanks. One solution might be to have a pair of these fish in a well-planted nano tank.
If you do have them in a larger tank, they'll help to control your snail population, as they love to eat baby snails. They are carnivorous by nature, so having a few baby snails to munch on as a snack is good for them! You can also feed them brine shrimp, krill, etc.
They will do well with water parameters in a "normal" or "mid" range - nothing to extreme. Make sure your water flow isn't too strong.
These little guys should be happy and healthy for at least 5 years or so, provided they have a well-filtered tank, places to hide, and lots of treats to enjoy!