Going out to sea is a standard for island tours, and the waters of Guam are also clean. However, there are many Japanese in Guam, and they are afraid of sun, bikini, and embarrassed. You don't have to worry about seasickness in Guam. First, the ship is big. Second, the boat basically does not have to go far, you can see a pile of dolphins. Its really a bunch. You can play this kind of kayak that is dragged by the boat and rush a small wave. Otherwise, you can snorkel, or you can squat on the boat.