According to the author of the video, ReubenMRU, what at first glance (minute 1:24) seems to be a waterfall under the sea in Mauritius, is only perceived from a certain height, "it is an optical illusion caused by the sand drag to the bottom of the sea due to water currents between the crevices of the reefs. "
In Absolutely Stunning Illusion of an Underwater Waterfall in Mauritius there are photos of the phenomenon, also visible from the heights of Google Earth.
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