If it were at my house, I think I'd try to figure out why the bulb is burning out so quickly, rather than trying to re-engineer something that might at one time have been functional.

Power supply driving bulb beyond 200 W?

System originally designed for lower power (say, 150 W) bulb, then incorrectly "upgraded" by previous owner?

Fan no good, or substandard replacement made by previous owner?

Blocked ventilation?

From what you describe, I'm assuming that you have one 200 W bulb that is pumping light to a bunch of locations in the pool through optic fiber. Is that right?

I have no experience with pool lighting, but I have used some small industrial fiber optic illuminators. They're 150 W, and they REALLY get hot if something messes up the cooling air flow.