kmsolo:I guess I'll just tip everyone! I'm diving in Cozumel and I'm pretty sure locals know American's tip (or most of us) If the DM or Capt feels wierd about me handing them some money then they can feel wierd. It's my vacation and I would feel wierd not tipping...
Thanks again for all the overwhelming advise.
~K
There was a thread in the Cozumel forum that concluded that $5 a tank was good there.