Stephen Keen
New member
OK, I know that I'm about to start WW 3 here but I think I can help clarify some things about using LED lighting for coral growth. Contrary to perception, lumen for lumen, MH lighting is considerably more efficient than LED lighting. MH lighting puts out more lumens, per watt of power, than LED by 25%. A 600 watt MH lamp, for example, creates 60,000 lumens. A 600 watt Lumatek digital ballast uses 550 watts of power. An LED fixture that creates 60,000 lumens uses 800 watts of power...it's true. The low wattage LED's out there simply do not produce as much lumens as MH . You can put a lower wattage MH and use less power too. You will still get more lumens per watt of power no matter what size bulb...but 1000 watt lamps are the most efficient.
An HPS can put out between 90-150 lumens per watt, once you add in ballast losses and reflector loss the result is 63 to 105 lumens per watt. So the lamps getting 100 lumens/ watt will produce 60,000 lumens at 600 Watts, really it is more like 660-680 watts including ballast.
An LED at temperature and continuous emission can produce about 75 Lumens per watt, or more like 68 lumens per watt including ballast. I used 75 watts per lumen as a guide. So at 800 watts time 75 lumens per watt = 60,000 lumens.
Also it is widely accepted that LED's create less heat....well this is true b/c they are consuming less power due to their lower lumen output, that is the only reason. But again if you are comparing apples to apples (lumens to lumens) LEDs actually create MORE heat. Watts equals heat whether it's your toaster, refrigerator, computer. This is the only reason why digital ballast make less heat than magnetic ballast, it's because they use less power.
This raises the question about why LED's even exist since they produce less lumens per watt. The reason is because MH lighting creates a spectrum of colors, some that can't even be seen. Plants only use a certain spectrum of light , so the unused color spectrum is wasted lumens. What they have figured out is that flowering plants use a mixture of 460 nm blue and 630 nm red for example, so they produce a LED fixture that consumes 400 watts of electricity but has comparable lumen output in only these 2 colors as a MH, this is how they claim "equal to a 600 watt MH". This also goes for commercial and residential lighting, again they are only creating visible light so they are more efficient in these instances. Let me say now that in fish only tanks, vegetative plant growth, commercial or residential lighting, LEDs are more efficient at producing the same amount of visible light for short distances.
LED's do not pack the "punch" that MH lighting has, in other words the ability for the lumens to make it to the bottom of your tank, or to penetrate a plant canopy to light lower branches. You won't see them mounted directly to a 20' high celling in a commercial building like you see MH.
The last advantage/disadvantage of LED's of that they do not produce UV. Some plants require UV light, and some don't. I don't know about corals, but fish don't require it, so in fish only tanks and to replace traditional lighting LED's are great b/c UV creates radiant heat. UV is the heat that is felt instantly on you hand when you stick it underneath a MH lamp...or even step out in the sun --not the air temperature, the warming from the light. The UV heats what it contacts and then these objects give off heat creating more heat in the environment. There are LED's available that produce UV that can be added but again you get back to the same conclusion, by the time you add these the fixture is producing heat and you are using lots of power.
Seedlings and small plants do great with the low stress of an LED to get them started but as they mature they need more lighting spectrums and some plants need UV to ripen properly. There is millions and millions of dollars spent a year studying plants, their growth, lighting and nutrition needs b/c it's a multi-billion dollar a year market that our lives depend on. Reef tanks on the other hand are a hobby that there is absolutely research being done about corals but frankly it doesn't have the funding that agriculture does. So what I'm trying to say is that YES indoor gardening of plants and fruits have benefited from LED technology, but it is b/c these LEDs are designed to be plant specific and what people don't know is that it has to be researched now how to feed the plants using LEDs instead and what temperatures the greenhouses now have to be kept b/c the lack of UV. UV makes the plants drink more and without it typically the grow rooms are kept warmer to try and maintain similar plant canopy temperature when using MH.
Here is my point....you can see how complicated this can get with all of this research needed for each type of plant to actually make them grow at the same rate using less power so can you imagine what a coral needs? What part of the spectrum of light does my red planet coral compared to my acans??? Who knows! I have 100 different kinds of corals in my tank from all over the world, do LED manufacturers claim that all of these corals use the same spectrum of light? So in order for LED's to be more efficient for coral growth it has to be determined exactly what a particular corals lighting requirements are so that only those spectrums are produced. Ok let's say they get it figure out and most corals use X nm mixed with X nm for optimal coral growth for a type of acan...is that color going to be attractive in your tank? Will that spectrum actually make the coral look cool? I can tell you the ones for flowering plants are a pink/purple color that I can't stand to be around, it's hard to adjust your eyes back to normal after being in an LED garden. What about UV? Do any or all corals use UV to grow? Do they use a little or alot? Do they use other parts of the lighting spectrum that isn't visible to us? I think there are too many corals to study individually to make LEDs viable to reef keeping as a hobby. The only viable application I could think of is for a specific coral, on a commercial scale to make it worth the cost, and not in a display.
Please understand that I'm speaking from experience, this isn't just stuff that I've read on the web. I'm also not arguing that people can't keep corals alive under them and that some people are using them just fine, I'm arguing that power consumption vs. power consumption MH will win everytime in our hobby. My company is a manufacturer of cutting edge gardening equipment so LED's have been on our radar for years. We have tested $3k fixtures that plants die underneath, I have also talked with several LED manufacturers about making us an fixture that is equivalent to a 600 watt light and I finally had a company going to build for me....but the problem is that it uses 800 watts of power. I'm very well embedded in the indoor gardening industry and we are privy to the newest technologies before they are even written about online, and LED technology isn't close to replacing MH lighting....especially considering they are 10x's the price for 1/2 of the lumens. You would have to use the fixture for 5 yrs to save enough money on electricity just to pay for it. My company manufactures water-cooled lighting equipment which increases the efficiency of cooling the heat they produce by 50%...this is how we are increasing the efficiency of using MH lighting. If LEDs were the future we would be manufacturing LED's, I have tried to make it work....it just isn't going to happen. How can you duplicate the sun without any heat?
With all that said...it will be a different type of lighting that I see in our future. Plasma.
http://urbangardenma...plant-lighting/
Thanks for reading!
An HPS can put out between 90-150 lumens per watt, once you add in ballast losses and reflector loss the result is 63 to 105 lumens per watt. So the lamps getting 100 lumens/ watt will produce 60,000 lumens at 600 Watts, really it is more like 660-680 watts including ballast.
An LED at temperature and continuous emission can produce about 75 Lumens per watt, or more like 68 lumens per watt including ballast. I used 75 watts per lumen as a guide. So at 800 watts time 75 lumens per watt = 60,000 lumens.
Also it is widely accepted that LED's create less heat....well this is true b/c they are consuming less power due to their lower lumen output, that is the only reason. But again if you are comparing apples to apples (lumens to lumens) LEDs actually create MORE heat. Watts equals heat whether it's your toaster, refrigerator, computer. This is the only reason why digital ballast make less heat than magnetic ballast, it's because they use less power.
This raises the question about why LED's even exist since they produce less lumens per watt. The reason is because MH lighting creates a spectrum of colors, some that can't even be seen. Plants only use a certain spectrum of light , so the unused color spectrum is wasted lumens. What they have figured out is that flowering plants use a mixture of 460 nm blue and 630 nm red for example, so they produce a LED fixture that consumes 400 watts of electricity but has comparable lumen output in only these 2 colors as a MH, this is how they claim "equal to a 600 watt MH". This also goes for commercial and residential lighting, again they are only creating visible light so they are more efficient in these instances. Let me say now that in fish only tanks, vegetative plant growth, commercial or residential lighting, LEDs are more efficient at producing the same amount of visible light for short distances.
LED's do not pack the "punch" that MH lighting has, in other words the ability for the lumens to make it to the bottom of your tank, or to penetrate a plant canopy to light lower branches. You won't see them mounted directly to a 20' high celling in a commercial building like you see MH.
The last advantage/disadvantage of LED's of that they do not produce UV. Some plants require UV light, and some don't. I don't know about corals, but fish don't require it, so in fish only tanks and to replace traditional lighting LED's are great b/c UV creates radiant heat. UV is the heat that is felt instantly on you hand when you stick it underneath a MH lamp...or even step out in the sun --not the air temperature, the warming from the light. The UV heats what it contacts and then these objects give off heat creating more heat in the environment. There are LED's available that produce UV that can be added but again you get back to the same conclusion, by the time you add these the fixture is producing heat and you are using lots of power.
Seedlings and small plants do great with the low stress of an LED to get them started but as they mature they need more lighting spectrums and some plants need UV to ripen properly. There is millions and millions of dollars spent a year studying plants, their growth, lighting and nutrition needs b/c it's a multi-billion dollar a year market that our lives depend on. Reef tanks on the other hand are a hobby that there is absolutely research being done about corals but frankly it doesn't have the funding that agriculture does. So what I'm trying to say is that YES indoor gardening of plants and fruits have benefited from LED technology, but it is b/c these LEDs are designed to be plant specific and what people don't know is that it has to be researched now how to feed the plants using LEDs instead and what temperatures the greenhouses now have to be kept b/c the lack of UV. UV makes the plants drink more and without it typically the grow rooms are kept warmer to try and maintain similar plant canopy temperature when using MH.
Here is my point....you can see how complicated this can get with all of this research needed for each type of plant to actually make them grow at the same rate using less power so can you imagine what a coral needs? What part of the spectrum of light does my red planet coral compared to my acans??? Who knows! I have 100 different kinds of corals in my tank from all over the world, do LED manufacturers claim that all of these corals use the same spectrum of light? So in order for LED's to be more efficient for coral growth it has to be determined exactly what a particular corals lighting requirements are so that only those spectrums are produced. Ok let's say they get it figure out and most corals use X nm mixed with X nm for optimal coral growth for a type of acan...is that color going to be attractive in your tank? Will that spectrum actually make the coral look cool? I can tell you the ones for flowering plants are a pink/purple color that I can't stand to be around, it's hard to adjust your eyes back to normal after being in an LED garden. What about UV? Do any or all corals use UV to grow? Do they use a little or alot? Do they use other parts of the lighting spectrum that isn't visible to us? I think there are too many corals to study individually to make LEDs viable to reef keeping as a hobby. The only viable application I could think of is for a specific coral, on a commercial scale to make it worth the cost, and not in a display.
Please understand that I'm speaking from experience, this isn't just stuff that I've read on the web. I'm also not arguing that people can't keep corals alive under them and that some people are using them just fine, I'm arguing that power consumption vs. power consumption MH will win everytime in our hobby. My company is a manufacturer of cutting edge gardening equipment so LED's have been on our radar for years. We have tested $3k fixtures that plants die underneath, I have also talked with several LED manufacturers about making us an fixture that is equivalent to a 600 watt light and I finally had a company going to build for me....but the problem is that it uses 800 watts of power. I'm very well embedded in the indoor gardening industry and we are privy to the newest technologies before they are even written about online, and LED technology isn't close to replacing MH lighting....especially considering they are 10x's the price for 1/2 of the lumens. You would have to use the fixture for 5 yrs to save enough money on electricity just to pay for it. My company manufactures water-cooled lighting equipment which increases the efficiency of cooling the heat they produce by 50%...this is how we are increasing the efficiency of using MH lighting. If LEDs were the future we would be manufacturing LED's, I have tried to make it work....it just isn't going to happen. How can you duplicate the sun without any heat?
With all that said...it will be a different type of lighting that I see in our future. Plasma.
http://urbangardenma...plant-lighting/
Thanks for reading!
