I asked this question to myself in this thread: http://www.reefcentral.com/forums/showthread.php?t=1953353
The answer is yes, but I'm waiting for feedback from the manufacturer.
DIY LEDs - The write-up
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The answer is yes, but I'm waiting for feedback from the manufacturer.
TheFishMan65
New member
1) I'm thinking that I may not need them out quite so far to the edges. And if I don't need them out so far, should I still keep the same LED count and just move them closer together or just remove the outer rows/columns altogether?
There is overlap at the center so that would imply more at the edges, but then you get loss from what spills from th tank. So IMHO equally space them.
2) Are 45-degree optics a good choice? Rapid also has a 65-degree option but I liked the idea of a tighter spread. But what do I know?
How high are you mounting them? That determins the spread as much as anyhting. See post 4994 IIRC on page 200 (25 post / page).
There is overlap at the center so that would imply more at the edges, but then you get loss from what spills from th tank. So IMHO equally space them.
2) Are 45-degree optics a good choice? Rapid also has a 65-degree option but I liked the idea of a tighter spread. But what do I know?
How high are you mounting them? That determins the spread as much as anyhting. See post 4994 IIRC on page 200 (25 post / page).
Optics Question
Optics Question
I plan on starting a 144 LED fixture over my 180 SPS tank. I need to keep the LED fixture within the current hood which will only give me a maximum height of about 10 inches above the water. Since the fixture will to so close to the water, I was planning on using C channel spanning the entire surface area to spread light over the entire tank. It will be a mix of 16 XP-G NW, 32 XP-G CW, and 96 XP-E RB.
Since the fixture will be so close to the water will optics be necessary? I can find 80 degree for the XP-E LEDs but could not find them for the XP-G LEDs. The tank is 24 inches deep. Would 65 degree be to narrow?
TBR701
Optics Question
I plan on starting a 144 LED fixture over my 180 SPS tank. I need to keep the LED fixture within the current hood which will only give me a maximum height of about 10 inches above the water. Since the fixture will to so close to the water, I was planning on using C channel spanning the entire surface area to spread light over the entire tank. It will be a mix of 16 XP-G NW, 32 XP-G CW, and 96 XP-E RB.
Since the fixture will be so close to the water will optics be necessary? I can find 80 degree for the XP-E LEDs but could not find them for the XP-G LEDs. The tank is 24 inches deep. Would 65 degree be to narrow?
TBR701
TheFishMan65
New member
You might be able to get away with no optics. Might want 80, but I expect 65 will be too tight.
LED Lamp Design
LED Lamp Design
Dear Forum,
I am truly amazed to see such a great forum here! I think this might actually be the best source of general LED lighting information I've seen anywhere.
Some friends of mine asked me to design them some custom LED lighting for reef tanks, so I wanted to try to find out some more information about them. I design custom open-hardware LED light fixtures for a living (http://saikoled.com) for hobbyists and DIY folks, and from reading up about the biology and physics involved here, I think that these tanks are just about as perfect an application of LED technology as any I can think of, so I'm very excited about the project!
What I am wondering is if perhaps one of you kind folks could help me answer a few questions:
1. Why do you think LEDs are better than metal halide? My impression is that MH emit a huge amount of power as UV which is essentially useless (and actively dangerous), and that they don't dim well. However, otherwise they are more efficient than an LED and are cheaper. One that seems particularly odd to me is that I keep hearing that *20,000K* MH bulbs are too blue! At 20,000K, it should be putting out the majority of it's radiation at 140nm, way, way past the visible range and far into the range where it's extremely dangerous to look at or even shine on your body!
2. How much can you get 10,000 lumen commercial LED fixtures for? I am absolutely confident that I can make an extremely nice one that I would happily sell for under $1500, likely less if I am making more than one or two. Thus, it's sort of a waste of my time to make my own if I can point my friends to one that is just as good and costs less!
3. What are good sizes for me to design for? I could make a 2' long, 5-6" wide fixture that puts out 10,000 lumens, or a 4' long that puts out 20,000 lumens, and so on. But I'd like to design them to be as close as possible to what a general aquarium user might actually want.
4. Is there anyone around who might be interested in collaborating to do this commercially? I have a lot of experience with building these fixtures, including dealing with problems that most newbies don't think about, like case design, heat dissipation (the more powerful the LED, the more the die heats up and must be cooled rapidly), spectrum tuning, nice user interfaces, wifi control, etc. I would love to find someone who knows about aquariums to work with.
Best wishes and a happy new year,
Brian Neltner
LED Lamp Design
Dear Forum,
I am truly amazed to see such a great forum here! I think this might actually be the best source of general LED lighting information I've seen anywhere.
Some friends of mine asked me to design them some custom LED lighting for reef tanks, so I wanted to try to find out some more information about them. I design custom open-hardware LED light fixtures for a living (http://saikoled.com) for hobbyists and DIY folks, and from reading up about the biology and physics involved here, I think that these tanks are just about as perfect an application of LED technology as any I can think of, so I'm very excited about the project!
What I am wondering is if perhaps one of you kind folks could help me answer a few questions:
1. Why do you think LEDs are better than metal halide? My impression is that MH emit a huge amount of power as UV which is essentially useless (and actively dangerous), and that they don't dim well. However, otherwise they are more efficient than an LED and are cheaper. One that seems particularly odd to me is that I keep hearing that *20,000K* MH bulbs are too blue! At 20,000K, it should be putting out the majority of it's radiation at 140nm, way, way past the visible range and far into the range where it's extremely dangerous to look at or even shine on your body!
2. How much can you get 10,000 lumen commercial LED fixtures for? I am absolutely confident that I can make an extremely nice one that I would happily sell for under $1500, likely less if I am making more than one or two. Thus, it's sort of a waste of my time to make my own if I can point my friends to one that is just as good and costs less!
3. What are good sizes for me to design for? I could make a 2' long, 5-6" wide fixture that puts out 10,000 lumens, or a 4' long that puts out 20,000 lumens, and so on. But I'd like to design them to be as close as possible to what a general aquarium user might actually want.
4. Is there anyone around who might be interested in collaborating to do this commercially? I have a lot of experience with building these fixtures, including dealing with problems that most newbies don't think about, like case design, heat dissipation (the more powerful the LED, the more the die heats up and must be cooled rapidly), spectrum tuning, nice user interfaces, wifi control, etc. I would love to find someone who knows about aquariums to work with.
Best wishes and a happy new year,
Brian Neltner
Sampo
New member
HI Guys and Gals, im setting up a 55G rimless 32x20x20 and i was hoping to build a DIY led fixture for it.
I started reading through the posts at the start of the tread and it seemed fairly easy, but now not so much.
I'm keeping a mixed reef and want to get as much color out of my corals as possible w/o using anything other than led's. And in the future i would like to hook the lights up to a controller to sim dawn/dusk.
Would one of you diy guru's mind helping me out, at this point i seriously needs some help.
Also as of right now i haven't ordered any part of the lighting system, was hoping for guidance before i spent any green on it
I started reading through the posts at the start of the tread and it seemed fairly easy, but now not so much.
I'm keeping a mixed reef and want to get as much color out of my corals as possible w/o using anything other than led's. And in the future i would like to hook the lights up to a controller to sim dawn/dusk.
Would one of you diy guru's mind helping me out, at this point i seriously needs some help.
Also as of right now i haven't ordered any part of the lighting system, was hoping for guidance before i spent any green on it
I think that you can use a splash screen and place the fixture 2" above water. In this case optics won't be necessary for sure.
A photo of the hood could help us.
widmer
Drug Enthusiast
I would almost always recommend optics, regardless of fixture height, especially when using the XP-series LEDs.
Optics will greatly improve the efficiency of the fixture by grabbing all of the light that's shining off to the sides, and the light that's hitting the water at too much of an angle to penetrate significantly, and will help to channel it down into the water.
Even if you don't feel like you need them due to the shallowness of your tank or fixture height etc, use them anyway and then you get to run your LEDs at a lower drive current and save more on the power bill etc.
The only situations where I would be hesitant to recommend optics, or would say really wide optics only are when either all of the LEDs are grouped into a very small cluster or when there is a lot of space between each LED.
Optics will greatly improve the efficiency of the fixture by grabbing all of the light that's shining off to the sides, and the light that's hitting the water at too much of an angle to penetrate significantly, and will help to channel it down into the water.
Even if you don't feel like you need them due to the shallowness of your tank or fixture height etc, use them anyway and then you get to run your LEDs at a lower drive current and save more on the power bill etc.
The only situations where I would be hesitant to recommend optics, or would say really wide optics only are when either all of the LEDs are grouped into a very small cluster or when there is a lot of space between each LED.
This is very good advice =) Optics are really good for improving apparent brightness... the only place they aren't is if you're including UV LEDs. I am looking at using some 400nm purple/UV LEDs, and the PMMA most lenses are made of would absorb a lot of the light. Otherwise, the PMMA generally only absorbs about 20% of the light passing though (i.e. 80% optical efficiency).
Brian
Sampo
New member
Ok, so im looking at ordering this, http://www.rapidled.com/servlet/the-58/36-Ultra-Premium-LED/Detail
But im interested if i should look into UV led's?
And should this be good for a 32x 20 x 20?
But im interested if i should look into UV led's?
And should this be good for a 32x 20 x 20?
onetrickpony
Premium Member
Just wondering, The buckpucks can only run 6 LEDs with a forward voltage of 3.5v or 21volts
any thoughts on running 7 of the XPGs with a forward voltage of 3.0 = 21 volts
any thoughts on running 7 of the XPGs with a forward voltage of 3.0 = 21 volts
TheFishMan65
New member
It should work from what I have read and understand. But I do not know of anyone that has tried it.
widmer
Drug Enthusiast
Sorry, not recommended unless you want to stay in that 350 mA or below range. Here, I clipped the pertinent chart from it's data sheet:
As you can see, even if you go up to ~500 mA, you approach 22 volts which is uncomfortably close to the very max Vf you should have your string of LEDs going. And of course @ 700 mA, you're at 22.5 volts, which is too much. Not to mention the natural variation in binning, under which blind probability gives you a 50% chance of exceeding this Vf as well.
The good news is that the XM series LEDs can easily allow you to drive those 7 LEDs at the Buck Puck's max current of 1,000 mA with plenty of elbow room. See the pic I grabbed from the XM data sheet:
Seriously though, presuming that reasonably-priced optics for the XM series are released soon, I'll be buying them for my next build. At cutter.com.au's website, they're currently $7.something each if you buy more than 10.
I didn't check that specifically, but I have a feeling that Cree MC-E optics can be used with XM-L.
der_wille_zur_macht
Team RC
Not sure about that. The MC-E is physically much larger.
That said, it's worth stating that you can pretty much at least TRY to use any optic on any LED. The worst that'll happen is you'll get a lot of spill out the sides if you're using an optic designed for a small (physically and angle-wise) LED on a larger one, and/or you'll get different widths. But even still, you can often correct these problems by raising or lowering the optic with respect to the LED. Not something you'd want to do on a billion LEDs for a big tank, but for experimentation or smaller tanks it's pretty achievable. Heck, right now, I have an XP-G running under an optic that was made for a 3-up Rebel.
That said, it's worth stating that you can pretty much at least TRY to use any optic on any LED. The worst that'll happen is you'll get a lot of spill out the sides if you're using an optic designed for a small (physically and angle-wise) LED on a larger one, and/or you'll get different widths. But even still, you can often correct these problems by raising or lowering the optic with respect to the LED. Not something you'd want to do on a billion LEDs for a big tank, but for experimentation or smaller tanks it's pretty achievable. Heck, right now, I have an XP-G running under an optic that was made for a 3-up Rebel.
TheFishMan65
New member
Thanks for doing the number Widmer. I was remembering the 3V point as being much higher.
spamreefnew
New member
does anybody here run without optics? How do i know if/or what angle optics to buy once my light is done and hanging above my 23" deep tank? will it be dark on the bottom? or will there simply be to much light shining on my walls?
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