I used to have a F8 puffer and he was in his very own tank. Curious, but aggressive. Any shrimp you put in there will be eaten.
Also, they are brackish fish, not freshwater. They may "survive" in freshwater, but won't "thrive" and live long. And by brackish I mean using marine salt mix, not regular aquarium salt.
There's more info in this forum about F8's:
http://www.thepufferforum.com/forum/index.php
Hope that helps!
