Heyyy! Bahamas is full of fish. You are better off staying away from the commercial places like nassau because its very touristy. Depends on how far you want to go, the most accessible is memory rock because it is so close and theres TONS OF FISH right there around 30ft. although walkers is pretty naked of places to go and stay on land from the hurricanes. All kind of depends on what you are looking for. I love the exumas, and abacoas.
It probubly wouldn't hurt having someone that knows the waters guide you, (depending where you go) but i assure you its not hard to find the fish, it just depends on free diving skills.