Be very careful to avoid salt creep on lighting. You can run into electrical issues, as well as having metal components of the lighting corrode and thus be ruined. Salt creep damage is not covered under warranty for your equipment! Your right it also decreases the effectiveness of your reflector.
I would highly recommend some way to prevent salt from getting on your equipment, be it through some sort of aquarium cover or lens cover over the fixture.
If this is not possible, then cool off your fixtures and delicately clean the salt off the reflector, bulb, and socket using a damp (fresh water) cloth or rag (used for fish stuff only, no solvents!). Clean them as often as you can.
-Diana