I can't see the puffer very well in the picture but I would guess a Hawaiian spotted puffer or Hawaiian blue puffer (aka papau toby). It is possible it is even a White belly puffer. Looks like he is in the Valentini or Toby family though. They don't get very big--4" or so. They are fun to watch. Love the Niger Trigger--we have one that is about 3 1/2" named Winston. He is quite the character!!