This dependable British-run outfit offers dives for certified divers (from US$50) and numerous courses, including the three- to four-day PADI Open Water course (US$380 including all materials). Colourful cichlid fish, the kind you've probably seen in a dentist's aquarium, swim throughout the lake, but more spectacular are the schools of dolphinfish that are drawn to your torch (flashlight) on night dives.

The bay's only dive operator, Aqua Africa also offers snorkelling gear (per half-day US$15) and has a very tasty cafe where you can fuel up with wraps and posh coffee as you learn your theory.