If you want to do some killer spear fishing (lion fish especially) go to Cay Caulker Belize and look up Ash (or just ask the first person you see when you get there where he is- they'll know).
We were scuba diving there with Ash's outfit and went out for lion fish with the rubber "three point" spears (easy and fun just watch the Loin Fish spines!) But our dive master nailed a 4 ft barracuda with his full spear gun. We watched him reel it it for a few minutes- perfect shot from 15 ft out!
We also dove (snorkled) for conk- got 4 lbs of MEAT! (But you can't scuba for conk- have to free-dive- which we did between scuba dives).
After we got in, they let me help clean it all (laughing at me trying to hammer the conk out of about a dozen large shells). When we were done they gave me a 5 gallon bucket FULL of ready to freeze/eat fish and conk- like 35 lbs!. I insisted on giving them about 1/2 of it, then tipped them another $80 on the spot.
I think we saved about $300 eating our OWN fish and conk (dropped off day one, and prepared nightly for four nights out of six by "Enjoy" restaurant a few blocks from our condo). They like to SLOW smoke most fish there-- right in front of you, while you hang on the swings and enjoy good drinks. And you can walk home afterward. Bliss!