Alternative FW lighting?

[dan2x38]

Was reading a SW post about LED lighting someone posted a site that makes LED light bulbs. Awhile back there was a big discussion about the power output of a bulb. Mostly it was discussed about the pigtail bulbs. When it states 13w = 60w it only looks that bright but it is still only outputting 13w. Is that correct?

OK I have a 2.5g Nano Planted tank. It is very tough to find light for something so small. Here is a link for a bulb that interests me: http://www.theledlight.com/12volt-led-bulb.html This bulb's power consumption is 2.5w with an estimated output of 25w. What is the actual output I need to be concerned about for overtop my 2.5g tank? Obviously 25w would be way to much!

[fischkopp]

When it states 13w = 60w it only looks that bright but it is still only outputting 13w.

It is only consuming 13W while it is putting out as much light as a conventional (incandescent) light bulb that would consume 60W. The same would count for LED light bulbs, although I doubt that they are suitable for a planted tank as their emitted light spectrum is usually quite limited (beside the high price).

[sniggir]

now that being said there are accual LED light systems that are being used in SW solaris makes them.. so maybe give it a try and see.

[dan2x38]

The tank is 2.5g. The depth is only 6" to 8" from point of light. I do not want kick ass lighting over top so the cost can be worth the output. My question is the real output only 2.5 watts? One watt per gallon would be great! I am looking for the translation of this bulb for my application? What alternatives are there to get 1 - 1.5 watts per gallon of light.

[kennyman]

To compare different lights on paper you have to find the luminosity and then divide the watt consumption into that to find a lumen:watt ratio. Then you need to look at the spectrum emission and compensate for differences in the percentage of output in the known Par wavelengths. And then reapraise the lumen:watt ratio making some kind of adjustmet for difference in par.

Pretty darn complicated imho 

Even though Lumens is the amount of light output it does not factor in how much of that output is being put into the various wavelengths that plants utilize for photosynthesis. That is what those graphs are all about. Showing peaks and valleys at differint points.

[dan2x38]

What I am trying to wrap my head around is if the LED bulb from the link is 2.5 watts or 25 watts output? Am I missing the point?