This is a small public beach that's protected by a breakwater. It's right next to a bunch of private resort beaches (also protected by a much longer breakwater) and the super-tacky Mambo beach, which is a combination beach/shopping mall. We entered the water at Marie Pampoen Beach and since the water was pretty choppy outside the breakwaters, we swam along the inside of the long rubble breakwater protecting the resort beaches. The bottom was mostly sand and the rubble of the breakwater had almost no coral on it, but there were a reasonable amount of fish.
When we returned to our entry-point, we ducked out from behind the shelter of the breakwaters and swam back on the outside. There was much more coral and fish here. In hindsight, I probably would have braved the choppy water and spent more time out here instead of in the calm, but somewhat-desolate sheltered area.