But even if they aren't dwarfs, and are in fact green spotted puffers they are not freshwater. It sucks I know, they are so cute and full of spunk. Unfortunately these poor fish suffer more from lack of good information in fish stores than any other species I have seen personally. While they may be able to live in freshwater for a limited time, their health and vigor will never reach their full potential if they are not gradually acclimated to brackish and then eventually marine conditions as they reach full maturity. In fresh they gradually waste away.
Its almost impossible for the guys at the fish shops to know everything about every species, most of them have a broad general knowledge that could help you keep many common species successfully. Puffers are an oddball fish most them dint have a whole lot of experience with passed keeping them alive in the shop for the week it takes to move them.
There is an information page about green spotted puffs in the puffer pedia and this article
http://www.thepufferforum.com/forum/lib ... s/#more-27 is a gem if find you cant resist those cute little faces and want to provide an awesome home for one of these personable little characters. A brackish tank may sound complicated when you read it at first, but once you get it down it really isn't so much to handle. The cute face happily greeting you like a little underwater puppy makes the extra efforts more than worth it.
Some call it a product of a mis-spent youth, I call it Rock n Roll ! 
