This LED lamp vs PC lamp

[neanderthalman]

Alllrighty, the article was shorter than I had expected, and I am reasonably impressed with their methods. They didn't use only an infrared thermometer, but a mercury thermometer as well. While much better than the infrared thermometer, the mercury thermometer requires reading by the human eye. This makes it prone to error, and a typical lab thermometer has a maximum precision of 0.5K. So, any heating by the solaris must be less than one half of a degree Celsius (or about one degree Fahrenheit). That's impressive, but it's also around what I'd expect. What WAS surprising was the temperature of the fixture. The top vents were kept barely above room temperature - I anticipated it running at least five to ten degrees above room temperature, due to the 50 C junction temperature of the luxeons.

 

Unfortunately, it didn't address spectral shift, which is known to occur in luxeon LEDs. They did measure the spectral purity of the solaris when new, and I am VERY impressed. Compared to the 20K XM bulb, the solaris produces less PAR, which contradicts PFO's claims. It's close, but not quite there. Interestingly, however it made up for the reduced PAR in it's spectral purity. In the end, it appears that the solaris produces more PUR than the 20K XM. Of the PAR produced, more of it is actually usable by the zooxanthellae, making the solaris superior to the MH.

 

Even more interesting is something they didn't consider, which was how the light intensity drops off with distance from a point light source. With MH, the intensity will drop off proportionally to the square of the distance. The solaris (and other LEDs) won't lose as much intensity with distance, due to the cone-shaped emission. That will preferentially reduce the amount of PUR from the MH in deeper areas of the tank, while the light from the solaris will penetrate much better.

 

Strangelove, you're making me want the solaris again. Bastage.

[strangelove]

Ahhh, see I wasn't just whistling dixie. And with your know how, making a Solaris style light should be no problem. I can swing a hammer and use a circular saw, but my problem is I can't wire a simple electric circuit. So I have to pay for stuff you guys can make, bit of a trade off either way.

 

Yeah it's pretty interesting how they can run the lights so cool, from what I can tell the heatsinks, which are huge and run the length of the light fixture, are in direct contact with the semiconductor side of each bulb. By the way PFO claims 11 years lifespan on these LED's, I cut that in half just to be on the safe side.

[HecticDialectics]

As for heat transmission, it's as close to zero as you can get. The Solaris that I have on my tank adds no heat to my system, heat that I can detect.

 

I'd bet that the heater just turns on less... if you have a heater that is, but 75W just isn't very much power to have over a tank anyway. To be fair, venting most of the heat out of the top and sides would definitely make the heat gain a lot lower.

 

They did measure the spectral purity of the solaris when new, and I am VERY impressed. Compared to the 20K XM bulb, the solaris produces less PAR, which contradicts PFO's claims. It's close, but not quite there. Interestingly, however it made up for the reduced PAR in it's spectral purity. In the end, it appears that the solaris produces more PUR than the 20K XM. Of the PAR produced, more of it is actually usable by the zooxanthellae, making the solaris superior to the MH.

 

Even more interesting is something they didn't consider, which was how the light intensity drops off with distance from a point light source. With MH, the intensity will drop off proportionally to the square of the distance. The solaris (and other LEDs) won't lose as much intensity with distance, due to the cone-shaped emission. That will preferentially reduce the amount of PUR from the MH in deeper areas of the tank, while the light from the solaris will penetrate much better.

 

 

And what reflector did Dana Riddle use? haha A lumenarc would most assuredly cause the XM 20K to -blow- away the solaris. You can tell from the plot of the halide par that it was a crap reflector. What's the deal with people comparing a $175 MH setup with an $850 light fixture? I think a $300-$350 top of the line MH setup is much more realistic when you're talking about someone looking at an $850 led fixture as a lighting solution. A lumenarc also focuses the light over a broader area initially, meaning that the intensity drop from a point source would be less.

[strangelove]

I'd bet that the heater just turns on less... if you have a heater that is, but 75W just isn't very much power to have over a tank anyway. To be fair, venting most of the heat out of the top and sides would definitely make the heat gain a lot lower.

And what reflector did Dana Riddle use? haha A lumenarc would most assuredly cause the XM 20K to -blow- away the solaris. You can tell from the plot of the halide par that it was a crap reflector. What's the deal with people comparing a $175 MH setup with an $850 light fixture? I think a $300-$350 top of the line MH setup is much more realistic when you're talking about someone looking at an $850 led fixture as a lighting solution. A lumenarc also focuses the light over a broader area initially, meaning that the intensity drop from a point source would be less.

 

Most of the heat generated in the tank comes from a Rio 2100 for the return line, maxijet 900 for circulation, and a rio 600 for the skimmer. I have a Stealth heather in the tank which tuns on and off, so my tank would probably run cooler if I removed the heater. With everything running the temp is a stable 75 degrees. When I mean stable, I mean never rises never falls, constant 75 degrees for the past 3 months.

 

I've got SPS corals growing on the top of the tank, there are LPS corals growing in the middle of the tank, and I've got soft corals growing on the bottom along with an anemone. Had a clam, but think it got stung by a Galaxia coral that is growing very quickly on the bottom of the tank. None of my corals are overextended, polyps are spreading nicely, Picilopora is growing new branches and keeping it's green color, I've got an Acropora which is new to the tank and doing fine. The Frogspawn and Elegance corals are loving the light the Solaris puts out and have grown so quickly that I'll need to frag the frogspawn in a couple months and I'll need to make a permanent sheltered area in the tank for the Elegance since it's sweepers could be a problem.

 

So I'm not sure where you got 75w from, with the type of growth I'm getting from the variety of coral that I'm keeping I would put it on PAR with 250w MH bulb. There you go with the money thing again, you need to be able to think long term when you get a light like this. Sure $300 for a nice MH fixture, but every year you will need to replace that bulb, $80 bucks a pop. In five years of bulb changes will cost you $400. So just for your lighting you've spent $700. That's $150 dollars savings. Not much when you add the hassle of heat gain and power usage.

 

Also the Solaris takes less energy to run and the need for a chiller isn't needed. Most people using MH lights use a chiller which costs an extra $300 or so. So $700 for a light for 5 years + $300 for your chiller = 1,000 bucks. Also you need to figure in how much your chiller is costing you to run, another added cost.

[HecticDialectics]

So I'm not sure where you got 75w from, with the type of growth I'm getting from the variety of coral that I'm keeping I would put it on PAR with 250w MH bulb. There you go with the money thing again, you need to be able to think long term when you get a light like this. Sure $300 for a nice MH fixture, but every year you will need to replace that bulb, $80 bucks a pop. In five years of bulb changes will cost you $400. So just for your lighting you've spent $700. That's $150 dollars savings. Not much when you add the hassle of heat gain and power usage.

 

Also the Solaris takes less energy to run and the need for a chiller isn't needed. Most people using MH lights use a chiller which costs an extra $300 or so. So $700 for a light for 5 years + $300 for your chiller + 1,000 bucks. Also you need to figure in how much your chiller is costing you to run, another added cost.

 

 

75W was from Dana's article. I was referring to price -only- because so many people love comparing the Solaris output to a -horrible- MH setup. Like I keep saying, **a lumenarc will literally -double- the light output over a spider reflector.** Anyone willing to spend $850 for a Solaris is going to be willing to spend $130 to get a good MH reflector. Compare high quality to high quality... don't compare high quality to crap.

 

 

I don't feel like getting into strict cost comparisons, you already know my position on that from another thread.