Blackwood
Contributor
ReefMongoose:I guess I am arguing this from an academic point of view and not so much a real life point of view. I have yet to see how others justify their 2ATA answer though if it's not for the reasons I have mentioned above. If it is calculated simply because it is 33' below the surface and seen as analogous to an open water environment then I cannot agree.
Again: The cave is open to and in equilibrium with the rest of the water. It's one body of water.
If you want, you can prove it to yourself. Go fill up the sink. Take a styrofoam cup and put it face down into the water. Position it so that it's halfway into the water. Poke a hole in the top. See if water fills the cup or if it just fills halfway (so that it's at the same level as the rest of the water in the sink).