Jawfish hold eggs in their mouths until they hatch, and once every few minutes, will quickly spit them out (as here) and then suck them back in again in a split second, in order to make sure all of the eggs get plenty of oxygenated water.
Note the blue underside of their host anemone (Philippines)
Sunlight refracts at odd angles in the waters of cenotes, due in part to the high density and organic material in the water.
