Jellyfish Lake, Eil Malk Island, Palau, Pacific Ocean

- The anoxic layer that begins at about 15 meters contains high concentrations of hydrogen sulfide which can be absorbed through the skin of a diver which can lead to death.
Jellyfish Lake is currently the only one of Palau's marine lakes open to tourists.
• Safety considerations
Although both species of jellyfish living in the lake have stinging cells (nematocytes), they are not in general powerful enough to cause harm to humans. It has been reported that it is possible to notice the stings on sensitive areas like the area around the mouth. The Fish 'n Fins tour guide recommended that people with allergies to jellyfish consider wearing protective clothing.