Measuring output/wattage/spectometer?

Does anyone have a link I can read about measuring the output of my lights? I actually have access to a spectrometer- a chinzy one, but still!- but I'm a little foggy on what I'm supposed to be measuring for. My LFS says I may have "old bulbs", wants to sell me $$$$ new ones. I am willing to spend if I need to, but still a newbie and don't want to get ripped off. Thanks for any help!

 

What type of bulbs and what ballast ?

 

and how old?

 

It's a Aqualight Pro, HQI ballast, 2 compact fluorescents, 2 metal halide, and LED moon lights. I think it's about 8-9 months old. It's 48" if that helps. My LFS said since I don't grow alot of algae ( I already lost a long spine urchin- probably starvation), and I want to try some soft corals, I would need to replace the lights. Am I getting good advice?

 

The Aqualight Pro model to which you refer comes in a 2-150W, or 2-250W metal halide configuration. Either one would be suitable for most tanks. Many say that MH should be replaced after 8 months, but Tangster could tell you better.

Get a price from your LFS, then ask Tangster. He could probably hook you up with better bulbs at a lower price. That's just how he rolls.

 

Okay- now I'm getting it. Under replacement parts in the manual (Ohhh... the manual!), it says HQI double ended metal halide lamp 150 watt!! Tah Dah- and the light comes on...

 

You cannot test for output with a spectrometer....for that you need a PAR meter. Your spectrometer will tell you the spectrum that the bulb is putting out. As a bulb ages, not only does PAR go down, but the spectrum shifts.

Advanced Aquarist's Online Magazine - Feature Article: Poor Man's Spectrometer: Estimating Lamp Spectral Quality for Less Than $30 (This is the model I like.....the other one costs over $300)
Advanced Aquarist's Online Magazine - Product Review: A Comparison of Two Quantum Meters - Li-Cor v. Apogee (I used the Apogee)