There are often sand pathways called grooves in the coral reef.
.Spur and Groove is the term. The sand finds it's way to deeper water by wave action, surge. See the overhangs along the sides.
.Spiny Urchins wandering around. They move using tiny tube like feet that are longer than their spines on their bottoms. Their mouth is on their bottoms, too. They pick up food, don't ask me what, and shuffle it to their mouth. I read someplace that they're picky eaters!
Wonderful strange creatures! If you get close, they know you're there and wiggle their spines at you. They're quite helpless, you only get hurt if you bang into them. Not a good idea, you'll hurt the Urchin!
.Some funny sponges, I'm guessing "Viscous Sponge" P. angulospiculatus. Such a name!!! Ooooooo!
Thanks for stopping by!