Most puffers sold at LFS are salt water / brackish water fish. They may do well and CAN be acclimated to ajust to freash water but most times they don't do well and wither away.
There are a few taht are found or do well in aquarium conditions (freash water).
Unfortionetly it is not commonly found in LFS and they can be alittle pricey.
Here are three peffers:
Tetraodon cutcutia ( Malayan Puffer )
Range: malasia, and parts of India, in freash and brakish waters.
Habits: Quarrelsome towards other fishes and even among themselves.
Water conditions : Hard , akaline water with salt added, one teaspoon per 4 liters.
Food requirements ; live foods in larger sp. chopped shrimp, crushed snails are a delicacy.
Tetraodon palembangensis ( Figure -Eight Puffer )
Range : Southeast Asia and Malasia Penninsula
Habits : A fin nipper, tends to be pugnacious
Water conditions : Does best in water to which a teaspoon of salt per 4 liters has been added.
Food requirements : Prefers larger live foods like fishes or shrimp
Tetraodon Miurus ( Congo puffer ) FREASH WATER ONLY
Range : middle and lower Congo River, found in freash water only.
Habits : A dangerous fish in a community aquarium, should be housed alone or with other tank mates of its own kind.
Food requirements : Living small fishes, fully grown brine shrimp or pieces of earth worms, they enjoy snails.
those are the three I have done research on and kept the Miurus at one point. VERY aggressive little fish but tons of fun to watch. I added a small amount of salt anyways to keep the chances of ick which they seem prone to down.
Hope this helps,
Danny