Can I ask you something? Did you know that just off of the top of your head, so to speak?
NEVER UNDERESTIMATE THE POWER OF FREEP!
Yes, but just because of where I grew up and because of my travels.
I grew up in South Florida where every school kid has dissolved a piece of limestone rock he picked up in lemon juice. While tromping through the Big Cypress Swamp, you need to watch your step or you can be up to your hip in a mini-sinkhole.
As for the Yucatan and neighboring Guatemala, we spent three weeks traveling through the region two years ago and swam in the Cenote seen in the picture I posted.
The Cenotes communicate with each other through long tunnels dissolved through the limestone to form complexes like a termite mound. If one of those tunnels reaches the sea and surfaces at the sea floor, they are called "Ojos de Mar" ("Sea Eyes") and appear as sink holes on the seabed that have blurry water around them as the fresh water from the tunnel mixes with the salt water of the sea. While there, we snorkeled down to one those "Ojos de Mar" offshore of Puerto Morelos.