Ummm yes it can. The life will be shorter of the fish but it can be done. I want to know how. I heard the drip method was a good way? Some say though that the fish can't be 100% fresh but more to the brakish side?
^ X2, why would you want to make a fishes life shorter just to in essence suit your needs??? i mean i'm presuming if you have enough money to setup a tank for a nurse shark, so wouldn't you also have enough money to keep it running as a S/W tank as well???
I mean thats like saying; oh lets keep you locked up in a air tight room full of Co2 with only just enough oxygen in there for you to survive... i mean yea you'll still live, but your life will be significantly shorter...
There is only one other I can find speartooth shark, Glyphis glyphis but they are only found in Malaysia, Papua New Guinea, and Queensland, Australia. The bull shark is found all over the world. Even in the mississippi river. What other ones do you know of?