Guessing, I'd say about a 18 to 20 pound grouper.  I have Oliver, on "Dejarlo," to thank for this fish.  He spotted him first and then lent me his pole spear when the grouper took my sling spear into a hole.  The price for spearing him and working him out of the hole was a nasty Fire Coral burn on my arm.   Hey... if it was free and painless it wouldn't be half as much fun... err... or so I'm told.