Considering the Villa La Paloma in Cabo San Lucas?
A VT member wrote the following comment about visiting Cabo San Lucas:
Glass bottom boats by lil_traveller
It wasn't completely what I was expecting but it was still pretty cool. Sit in the boat and in the middle is a glass bottom and when you get to the deeper part of the ocean you begin to see some amazing fish and what not swimming up. It's pretty neat to see all the huge and brightly colored fish.