Though it is pricier, the night experience is far more colorful than the day, as the submarine's lights girve vibrancy to the colors of the reefs, fish, turtles, sharks and other creatures that float past the sub, often peering in the portholse (and looking as interested as the humans staring out). During the day, the scene is a wash of blue. Along with reefs, the sub visits an evocative shipwreck; all is narrated by the witty, and genuinely engaged, crew. An exceptional experience, especially for vacationers who don't scuba or snorkle. Note: The ride can be bumpy so skip this, or take medication, if you're prone to seasickness.