Lighting the Reef Tank

[fish head steve]

Please bear with me as I am out of my element here. Here are my questions:

How can the average home reefer know when bulbs actually need to be changed? Seems like it will vary from tank to tank depending on hours of use. I'm trying to avoid changing bulbs to soon or too late.

Is there an affordable but reliable meter suitable for home use that I can make base line readings after burn in and monitor the bulbs so I know when to change them?

I assume that the same meter could be used for all types of reef lighting--Halide, VHO, PC, T-5. If so, is the same approach used for all types of lamps? I run all of the above on 5 diffrent tanks.

Do you care to recommend a particular meter? I assume I want to measure PAR or PPFD--Yes?

Is anyone doing bulb analysis and comparison for lighting other than halide (Sanjay Joshi)?

Thank You~