Maybe not at full power but there is an awful lot of metal in those heatsinks to soak up the heat and with enough air movement it should work fine, given ambient temperatures don't get to high in the summer. Definitely install temperature sensors on the chips to monitor their heat, and point a fan behind each chip that draws in air from outside the enclosure or canopy and exhausts it out some other side.
Minimalistic multichip DIY LED build
- Thread starter maglofster
- Start date
TropTrea
New member
Yes you have a lot of surface area here for cooling. If my calculations are right and it is 72" long you have 2880 square inches of surface area which should be able to handle at least 600 Watts of LED's it they are properly spaced out without even using fans. But the secret is getting them spread out so they do create hot spots and cool spots. The other big issue is making sure that the bond between the heat sink and the LED's is solid enough to allow a good transfer of heat.
Personaly with this cooling method I'd be hesitent on using the 100 watt multichips. I would actualy use mainly 10 and 20 watt units. But you shouldn't have any problems with the 50 watt units if your very carefull on making sure they re properly monuted.
With a 400 gallon tank I would use at least 600 Watts of LED's and some people would go considerably over 800 watts considering that your going with dimmable drivers and probably will not have turned all up to max.
Note from your pictures you have a lot more overhead space then I have with most of my tanks. You can probably go with 60 degree lenses if you put your lights about 12" or more over the water surface. This will give you about a 39" beam diameter for each LED set at the substrate.
Personaly with this cooling method I'd be hesitent on using the 100 watt multichips. I would actualy use mainly 10 and 20 watt units. But you shouldn't have any problems with the 50 watt units if your very carefull on making sure they re properly monuted.
With a 400 gallon tank I would use at least 600 Watts of LED's and some people would go considerably over 800 watts considering that your going with dimmable drivers and probably will not have turned all up to max.
Note from your pictures you have a lot more overhead space then I have with most of my tanks. You can probably go with 60 degree lenses if you put your lights about 12" or more over the water surface. This will give you about a 39" beam diameter for each LED set at the substrate.
Spazdad
New member
The heat sink is only 38" wide. The hole of the tank on top is only 48". I was considering 600 just in DCs and that's saying 100w for each. I have plans to put a lot more on it. Hybrid actinic maybe some reds "love what they do to my nps" wanted to try the sunset panel from ac/rc and a few others. With a large 8" fan you guys think it's still going to be too hot.
iced98lx
New member
Getting decent SPS growth with my no-name chip at the moment.
I do have it cranked up decently high, which in turn caused an explosion of algae in my tank. Taking care of things with a skimmer addition finally.
Overall, I haven't seen anything that would suggest my multichip choice would be limiting or keep me from growing healthy coral. I had a par meter brought over, but due to LED variances I haven't posted numbers as they don't mean much- I was happy with them though.
I do have it cranked up decently high, which in turn caused an explosion of algae in my tank. Taking care of things with a skimmer addition finally.
Overall, I haven't seen anything that would suggest my multichip choice would be limiting or keep me from growing healthy coral. I had a par meter brought over, but due to LED variances I haven't posted numbers as they don't mean much- I was happy with them though.
Hey Ice,...interesting. I remember you were posting about running/controlling 16 channels. Can you put up a little more info on your build. I would be interested in your lighting duration times, maybe the fixture height off the water, what par you are getting at different depths and what corals are you growing. Thanks in advance,---Rick.....ps sorry for so many questions 
iced98lx
New member
Hey Ice,...interesting. I remember you were posting about running/controlling 16 channels. Can you put up a little more info on your build. I would be interested in your lighting duration times, maybe the fixture height off the water, what par you are getting at different depths and what corals are you growing. Thanks in advance,---Rick.....ps sorry for so many questions
No worries Rick.
Right now I've got 1 chip running (I have 3 cannons built, though) and controlling each of the 5 channels independently.
The build for the controller and light is here:
http://reefcentral.com/forums/showthread.php?t=2250389
I'm using a generic Ebay multichip with 5 channels
mounted and hanging over my test tank (29g biocube)
I had great success with all sorts of birdsnest, a few Millepora's and a bunch of LPS. Par wise I was at about 200 at the sand during peak output times, without much falloff left to right front to back. (mostly because big light + small tank)
I had a heater malfunction with my controller so I'm rebuilding the stocklist but it's keeping a pink Millepora happy at the sand bed at the moment.
as far as levels, my light constantly shifts throughout the day, based on this curve:
(anything negative is outputted as 0, the bottom scale is 0->24 being the hour in the day)
the blues peak at about 70% power, with the whites at 60% and the UV at 50% at peak. I haven't yet taken advantage of being able to dim each white separately, or each blue. (really, 3 channels would have been fine: white/blue/420nm).
Not sure how I'd run them if they were at the same level the whole day, this is such a big gradual curve you hardly notice that they're different throughout the day, and suddenly they're off! Going full dark over night, if that matters.
any other questions, let me know, glad to share my findings.
Thanks Ice,... let me wrap my brain around your info, and I might have another question or two. Going to read your build thread. I have been thinking about a frag tank with three 50w DC. I'm thinking of spacing them equally with dividers between the lighting. What I want to do is move the corals to brighter sections as they acclimate. I was thinking about a coral-x that would give me the 15 channels to control it with.---Rick
TropTrea
New member
Doing some recalculating from your data and better look at the pictures of your heat sink I get roughly 2,600 Square inches of cooling surface. Without fans I would not think twice about putting in 490 watts of LED's in there. With adding 4 8" fans from the top blowing into the fins from the top you should be able to comfortably handle 740 Watts of LED's. Pushin it to 800 Watts may or may not work you would have to monitor the temp of the LED's very closely.
Now mind you this is considering your running everything at full power. If say you have 400 watts of Neutral White LED's in the system but only ruin them at 40% of full power than you talking only 160 Watts of White LED's heating up the system.
Another thing to keep in mind is the effeciency of the LED's. I'm calculating off of the base of 70 lumn per watt so you would have something arouind the equicelent of 52,000 lumns. Which is extremly bright. If you used ore effecient LED's you would up to 74,000 lumns as it is not uncommon today to find the latest LED's pushing over 100 lumns per watt.
Yes I know that lumns is a usiless measurement but I'm just using it a comparison to the range of light you can get from that much wattage.
Note when I look at you running the minimium of 600 Watts and Ideal of 800 Watts I'm looking at that 70 lumns per Watt effeciency which is average for most multi chips. If you ran the 100 lumns per watt LED's you would only need 420 to 630 Watts total light.
TropTrea
New member
This is dependent on which series your looking at. In most cases your talikin a 5 or 10 watt chip that is run at a much lower wattage to get that kind of effeciency. As a example I'm running 5 Watt chips at 1,400ma and barely pulling 100lm.w. But yes if I ran them at 700ma I would get more lm/w however less lm per chip. Simularly most of the 50 and 100 watt multi Chips are not that as good on the effeciency range as th single chips are.
miatawnt2b
New member
Mr Wilson,
I apologise if this has been asked already, I couldn't seem to find my answer here or in your build thread.
What LED's are you using for your frag tank, and are you seeing good color and growth?
-J
I apologise if this has been asked already, I couldn't seem to find my answer here or in your build thread.
What LED's are you using for your frag tank, and are you seeing good color and growth?
-J
quiksilverchin
New member
I am building a led bar with (10) 10 watt Blue Led Chips. They all run at 12VDC and go for 1050 mA. To power this light, do I need to buy a power supply that can run at 12VDC and put out around 10Amps or would I read that using a Mean Well LPC 60-1050 constant current driver would work too. It runs at 9-48V and gives out 1050 mA
TropTrea
New member
I'm not sure what LED's your using. But if they are rated for 12 Volts at 1050ma then you could run 4 of them off of each LPC 50- 1050. It would probably end up cheaper in the long run than trying to find a Current regulated DC power supply to hadle the entire string. But check your LED specas Cree's 10 Watt Chips run at 3,000ma and roughly 3.4 Volts each.
reefpatrol3
New member
Would it be possible for someone to list a complete parts list to make a single 100w dream chip, or is that against the rules ?
reefpatrol3
New member
Can you use a flat sheet of aluminum and mount all the LEDs (100 watt dream chip and several 3 watt chips) but use one of the coolers listed in the previous pages mounted on the other side just above the dream chip? Will it cool it enough ?
Thanks
Thanks
Crazy_Beaver
New member
Hello everyone.
I ve spent some time the last days reading through the tread and firstly I have to say a big bravo to everyone that has contributed.
Now that a few people have some experience with the multi-chips how many do you suggest using on a 51X39X25 tank that will be mostly sps?
I saw a friends tank (55x24x24) and he used 4 50W with 60 degree optics and his coverage was quite nice with no light spillage!
He suggested 8 50W with 60 degrees optics in two lines of four for mine as one option or 8 in 3 lines (323) with 60 degree optics for the outer lines and 80 for the inner line.
My lights will be hung 18-19 inches from the waterline.
Watching Mr.Wilson's I was amazed that he lit an 8x3 with 3 or 4 100's but then again his tank is half shallow compared to mine.
Now as I spent quite a lot of money for my current light I dont wanna walk a blind path if I ll make the switch,so any opinion - suggestion will be greatly appreciated!
Greetings from Athens
Loukas
I ve spent some time the last days reading through the tread and firstly I have to say a big bravo to everyone that has contributed.
Now that a few people have some experience with the multi-chips how many do you suggest using on a 51X39X25 tank that will be mostly sps?
I saw a friends tank (55x24x24) and he used 4 50W with 60 degree optics and his coverage was quite nice with no light spillage!
He suggested 8 50W with 60 degrees optics in two lines of four for mine as one option or 8 in 3 lines (323) with 60 degree optics for the outer lines and 80 for the inner line.
My lights will be hung 18-19 inches from the waterline.
Watching Mr.Wilson's I was amazed that he lit an 8x3 with 3 or 4 100's but then again his tank is half shallow compared to mine.
Now as I spent quite a lot of money for my current light I dont wanna walk a blind path if I ll make the switch,so any opinion - suggestion will be greatly appreciated!
Greetings from Athens
Loukas
TropTrea
New member
I do not think there anything like a said perfect situation on this for anyone. Different individuals like different lighting aproaches. You could go with 2 very high powerd pendents if you want maximium sparkle and want a high contrast level between the areas directly light and the shadows. Some people love that look. Then you can go with more light sources of as many as 16 pendents on your tank if you like a very evenly lighted tank. Some would love this others would consider if boring without any sparkle and minmal shadows.
For a refernce of your friends tank your tank is slightly larger. So if you like his lighting effect you should look very simular going with either 6 or 8 lights simular to his. If you want the lighting more uniform and less noticable shadows then go with more lights. If you want more sprakle and contrast go with less. But you have a starting reference to judge against your personal taste.
Another think to consider is that with your larger tank you will need closer to 300 watts or more total if you use the same pendent design. If you change your pendent design there can be a difference in the effeciency of your units so you will need to compensate for that.
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Hey guys. I need some help on a multi-chip build for a 16 gallon nano reef. It needs to support a clam at the sand bed and sps through out. I have one RapidLED Par 38 bulb and I was thinking about buying another bulb and hanging both over the tank and calling it a day.
I have been happy with the color of the par38 bulb. 6rb, 2nw, 2cw, 2uv all cree except the uv and run at 650ma.
Now I'm thinking of going the multichip route to keep the size down. I was thinking 2 30 watt chips or 2 50 watt chips dimmed down. Would two 30 watt chips be enough for that tank? What chips should I use? I cant seem to find them with uv in them.
Thanks for the help in advanced.
I have been happy with the color of the par38 bulb. 6rb, 2nw, 2cw, 2uv all cree except the uv and run at 650ma.
Now I'm thinking of going the multichip route to keep the size down. I was thinking 2 30 watt chips or 2 50 watt chips dimmed down. Would two 30 watt chips be enough for that tank? What chips should I use? I cant seem to find them with uv in them.
Thanks for the help in advanced.
