Ahihi Cove is a marine life preserve, so fish, shells and coral are protected. You can find plenty of fish, sea turtles, eels and occasionally dolphins and Tritons Trumpet. Definitely go early in the morning (7ish) so you can get a good parking spot and do not go if there is a south swell or waves over a foot, otherwise vis will be low. The coral heads are amazing at this location and the turtle cleaning station is an awesome experience. On the south end, just around the cove, there is a large school of blue stripped snapper that you can swim through. Take your UW camera!