Originally Posted by You
Can anyone tell me what the difference is between a glass bottom boat and a semi sub? We are looking at Naussa Bahamas and the cruise offers glass bottom boat excurions, and I found an independent operator, sea world tours, that offers semi subs.
>> A glass bottom boat is just what the name implies -- a boat of shallow draft with a pane of glass in its (flat) bottom through which you can look to see fish and other marine life. You are seated above the waterline. Expect to feel a lot of motion if you encounter moderate seas. Most glass bottom boats do have canopies over the whole passenger area and interior gunwhales around the glass bottom configured so that sunlight cannot strike the glass. Nonetheless, bright daylight conditions can affect visibility. You probably won't be able to see the bottom in a glass bottom boat.
>> A "semisubmersible craft" is a much larger vessel with a deep hull and a passenger compartment below the waterline where passengers sit two by two and look out through windows in both sides of the hull. The deep draft allows these vessels to handle moderate seas very well. The vessel does not actually submerge, but there's very little external light in the hull compartment so the view of the marine life is excellent. In shallower areas, you'll be able to see the bottom, including reefs, wrecks, and discarded tires that serve as marine habitat.
Of the two, I would opt for the semisubersible craft unless you have moderately severe caustrophobia.