bang guy
Moderator
Hi Mr. Angelfish 
I do understand you point. For your reef, I'd suggest you simple get a list of desired and let the Sharks suggest some lighting.
But, I do want to continue the debate I think it's a good discussion.
My point is that Lumens does NOT equal light output. Lumens are a measure of light around the wavelength that is brightest to the HUMAN eye. It is not a measure of light output, just how bright it will appear to a human. The coral in our tanks could care less how bright the tank is. If that were the case we would all be using High Pressure Sodium bulbs because they produce far more lumens than anything currently in the hobby. Try it if you like You tank will be a very bright, greenish yellow and you will not be able to grow light demanding corals.
A perfect example is the VHO and PC comparison you did. Take a VHO Actinic 110 watt putting out 1000 lumens. And your PC 55 watt dalight putting out 5000 lumens. The only light put out by the Actinic that shows up on the LUX meter will be errant light produced because of faulty phosphors. This only makes up a small percentage of the phosphors. The vast majority of the light is produced near the 430nm wavelength, which will NOT be picked up at all on a LUX meter. In other words, if someone created a perfect Actinic Phosphor the bulb would not produce any Lumens at all. And yet I know I could grow many types of coral under it.
From what I understand the LUX meter will pick up light falling near the 557nm range. Although this light is somewhat useful for coral it's not very pleasant to look at and you would need much more of it to produce the same growth patterns.
For what it's worth, The IceCap ballast will light 4 110 watt VHO bulbs using less than 290 watts of power, including the ballast consumption.
Are you beginning to see my point yet?
Guy
I do understand you point. For your reef, I'd suggest you simple get a list of desired and let the Sharks suggest some lighting.
But, I do want to continue the debate
I think it's a good discussion.My point is that Lumens does NOT equal light output. Lumens are a measure of light around the wavelength that is brightest to the HUMAN eye. It is not a measure of light output, just how bright it will appear to a human. The coral in our tanks could care less how bright the tank is. If that were the case we would all be using High Pressure Sodium bulbs because they produce far more lumens than anything currently in the hobby. Try it if you like
You tank will be a very bright, greenish yellow and you will not be able to grow light demanding corals.A perfect example is the VHO and PC comparison you did. Take a VHO Actinic 110 watt putting out 1000 lumens. And your PC 55 watt dalight putting out 5000 lumens. The only light put out by the Actinic that shows up on the LUX meter will be errant light produced because of faulty phosphors. This only makes up a small percentage of the phosphors. The vast majority of the light is produced near the 430nm wavelength, which will NOT be picked up at all on a LUX meter. In other words, if someone created a perfect Actinic Phosphor the bulb would not produce any Lumens at all. And yet I know I could grow many types of coral under it.
From what I understand the LUX meter will pick up light falling near the 557nm range. Although this light is somewhat useful for coral it's not very pleasant to look at and you would need much more of it to produce the same growth patterns.
For what it's worth, The IceCap ballast will light 4 110 watt VHO bulbs using less than 290 watts of power, including the ballast consumption.
Are you beginning to see my point yet?
Guy
