When I saw a green Spotted puffer at the fish store I wanted one so bad! And I wanted a freshwater tank so it seemed perfect! But the guy told me that they don't do as well in freshwater as they would in salt he pointed to some of the sickly ones and said thatw was why. When they're young they can live in freshwater, but they don't have a good chance of survival. He also told me which I read online later on, that the green spotted puffers eat the fins off of other fish. Adding 1 plus 1 together I realized that green spotted puffers wern't the fish for me! And later on when I couldn't find any freshwater fish that looked as nice as saltwater I got a saltwater tank!