Akumal is a great snorkel spot with the amazing Yal Kul Lagoon , and Half Moon Bay , both of which have had countless sea turtle sightings. Yal Kul Lagoon is a mixed water lagoon, with sweet water from the underground river system, and an inlet from the Caribbean Sea allowing the sea water to mix with the sweet water. This creates a kind of shimmery oil effect that is rare to see, and in turn creates an eclectic variety of underwater creatures, and coral to check out. The mix of lagoon and sea water gives way to a great variety of fish, coral, and plant life. Angel fish, Blue Tang, Spotlight Parrot fish, and Needle Nose fish, pass by your snorkel mask in hordes and in the clear waters below you can see Symmetrical brain coral, Firebox coral, and Lettuce coral. If you venture out of lagoon towards the sea you may be lucky enough to see a sting ray or a turtle or two. The best time of day is to go early in the morning to beat the crowds and ensure that the waters are clear to see the amazing variety of sea life. Please note only biodegradable sunscreen can be used in the lagoon. They actually prefer you to wear a t-shirt and hat in lieu of sunscreen as all creams and lotions can be harmful to this unique environment. Showers are available on site in order to rinse off harmful body products prior to entering the lagoon.