Hi, Cozumel is blessed with constant currents (stronger underwater) that keep this beautiful transparence of the water and its colors. There are places you snorkel where you are actually taken by the current (very mellow...no danger) and do not need to swim to get a great "movie" like insight. The same applies to SCUBA diving in Cozumel, for example on most walls/drop offs you dive there is no fin-work required, you just go with the current. Local snorkel and dive guides are very aware of this situation and will lead you through it. It is best to stay with a guide, they know every square meter of the area and can provide you with very useful hints and information. Good luck!