Please help me stop my roommate from killing himself.

Ok maybe not so dramatic, but I got your attention right?
My roommate went all Gung-Ho and bought some spear guns off craiglist. He's never spear fished a day in his life. He's a little over excited and it talking about going out blindly looking for fish. So far, the conversations have gone like this.

Me: So, what's your plan...
Him: I dunno, just go out in the bay and look for fish
Me: You'll probably get run over by a boat
Him: Nah man, I'll I've got the buoy, i'll stay by it
Me: 1) Not everyone, maybe not even half of the people in the bay are smart drivers. 2) You're right, all the fish in San Diego will gather right under your buoy waiting to get shot
Him: Eh



Him: Hey, you know anything about spear fishing?
Brent @OEX: Yeah, I know about it
Him: What's the average size fish you catch in the kelp
Brent @OEX: I don't shoot at anything less than 50#
Him: Nice man, I'm bringing home 50# tomorrow from La Jolla
Me: Yeah, cause everyone goes and shoots 50#'s all day long...
Him: Bro I got this
Me: So, did you buy an anchor or anything
Him: Nah, I think I'll just somehow tie my kayak to the kelp
Me: /facepalm


Me: So, show me how you hold the gun
Him: (Holds it like an m16)
Me: So what you're saying is you don't want to keep your fingers?


So, these are just a few short conversations of the many things we've discussed. What I'm asking here is, if anyone into spear fishing (I'm not experienced) wouldn't mind taking my buddy out and showing him the ropes? He's a really nice guy, eager to learn, charming, likes long walks on the beach and candle lit dinners.

Let me know. He's got everything he needs, just some direction.

Thanks all!