DIY LED Using 10 Watt Arrays
 

Decided to document what I'd like to do with respect to LED lighting for my 77 gal tank. I've been fence sitting for some time watching various builds etc & finally decided to do a bit more than experiment, although this is really still just that, an experiment. While I'd love to get my hands on something like an EcoTech Radion, they're just a bit too rich for my budget at the moment. I have some knowledge as far as electrical gear goes, so a DIY lighting fixture should not be a problem & save me a few $$ in the process.

I'm not a fan of builds with massive heatsinks and have been looking for a somewhat lighter & more elegant solution. Some of the more costly commercial fixtures like Radion, Orphek, Kessil have caught my fancy since they seem to be able to get the job done without a 50lb piece of aluminum to draw heat from their LEDs. A reasonably sized heatsink with a fan or two is more to my liking.

Inititally I'd been looking at an MR16 two pin bulb solution. They're designed to run off 12VDC, so with a 12 Volt power supply, some MR16 LEDs & sockets to plug them into, I figured that would be a good way to go. Have a few 4 watt (4 x 1 watt) MR16s in cool white as samples that I'm using above the kitchen sink as task lighting.

https://public.blu.livefilestore.com...96e.JPG?psid=1

These are great little lamps with heatsink & current limiting circuitry incorporated, but they do seem to run a little hot after being on for a while, so not sure whether they'll last the advertised number of hours before giving up the ghost. So far so good, perhaps the heatsinks are doing their job & my fears are unfounded. There are few to no threads on anyone using these over their tank, FOWLR, softie, LPS or SPS. Nevertheless, I'll keep my options open, since once the sockets are wired up to a 12 VDC supply, they're plug & play, easily replaced. Worst case, I can even disassemble them & replace the individual LEDs.

Since I'm on a 12 VDC kick as far as power supplies go, I've decided to pursue the 10 watt LED array route. Several manufacturers are now using similar arrays as a LED option for aquariums. Arrays can be had that run at over 100 watts. They're now available in many different colours, including UV & combo colours on the same chip. The combo chips are an interesting development since they should minimize the disco ball effect reported from many builders using individual 3 watt LEDs of different colours. They all use between 9 & 12 VDC running at 900 to 1000 mA. So close to 10 watts each at the rated voltage. I already have 4 cool white (6,000 to 7,000K) versions of these. 10 Royal Blues came in the mail yesterday & ten 10,000K arrays are enroute. Should be plenty for my 77 including spares.

https://public.blu.livefilestore.com...43e.JPG?psid=1

Now to the heatsink issue. I already have two small heatsinks with fans designed specifically for these arrays & 10 more on the way. What I'm thinking is to use two aluminum rails in parallel & screwing these heatsinks into them. The heatsinks will span the two rails & serve to hold them together. I'd like to tap the heatsinks & mount each array with two screws in addition to using heatsink compound. Even with the tiny fan, these are very light, so the fixture should be light & open for air circulation as well.

https://public.blu.livefilestore.com...2e2.JPG?psid=1

Last but not least, there are optics available to fit over these. I'm thinking of trying without to start & go from there. Here's a pic with all the goods(except the power supply).

https://public.blu.livefilestore.com...42e.JPG?psid=1

Stay tuned.

Going to follow along on this build.
What is your projected cost, finished?

Components I have (& on order) so far cost roughly $260. That includes 4 cool white arrays (6,000-7,000K), 10 Royal Blue arrays (452-455NM), 10 10,000K arrays, 12 heatsinks with built in fans, one 250 watt 12 VDC power supply & 2 sets of optics with holders. Probably won't use all 10 Royal Blues & may order some regular blues and/or the odd red, green, UV, combo array. Should be able to keep it between $300 & $400 I reckon. These are not Cree emitters & I don't care to get into the lumens for your buck debate here. I don't have much in the way of SPS coral and am confident that these generic arrays will do the job nicely for my LPS, softies & couple of SPS frags. I'm not in the coral farming business & provided there's moderate growth & the tank is pleasing to the eye, I'm good.

Still need to get the aluminum rails/supports, additional heat sinks and perhaps more power supplies & optics. Depending on how the power supply I ordered works, I may need to add current limiting drivers so as not to overdrive the LEDs. A couple of variable resistors are an option for dimming & limiting current, but those don't cost that much. Other miscellaneous hardware & wiring.

The optics & holders I have at the moment are actually the wrong size for the 10 watt arrays, the lens is probably ok, but the opening in the plastic holder looks to be designed for the higher wattage arrays, from 20 watts up. So I might just order a higher wattage array & see how that looks.

If you're looking to keep costs down...look to Donald's machine for the rails. One of the owners has a reef tank and they are priced much better than the big box stores.

Tagging along.

Hey thanks Mark. Last bunch I used to fabricate my current MH/T5 setup I got at Princess Auto in Kelowna. I assume Donald's machine is in Vernon?? NM, found it in the Vernon phone book.

Time for an update. I've got a little more work done on this. SeaHorse Fanatic has a similar project going built by a friend of his. This is what provided the motivation for me to finally get started on a LED fixture for my system.

http://www.canreef.com/vbulletin/showthread.php?t=81619

I checked out the local machine shop for aluminum stock that mseepman recommended, but they only had larger, thick material & I'm looking to keep the mass & weight of my build to a minimum. They recommended I try another local machine shop, but I was on my way to Kelowna that day anyhow, so went to Princess Auto where I had scored some reasonably priced square & angle stock before. Ended up getting some thin 8 foot lengths of 3/4 aluminum angle for about $15 ea incl taxes.

I haven't made up any kind of plan on paper or otherwise, kind of doing it on the fly. Still waiting for heatsinks, power supply & additional LEDs I've ordered, customs is taking their time in processing the shipments. grr. Since I have the aluminum & hardware to get started, I put together one 4 foot rack with two heatsinks.

https://public.blu.livefilestore.com...69e.JPG?psid=1

Had some thicker angle stock left over from building my MH/T5 rack, so used those pieces at each end of the lighter stock. Threaded with 8-32 tap & used stainless bolts to fasten.

Here's a detail view of the business side of the heatsinks with 10 watt LED arrays loosely positioned. Will endeavour to keep the wiring neat & tidy, using small terminals or soldering wires together & covering with heatshrink tubing. I'm thinking heatshrink will provide protection from moisture, but we'll see.

https://public.blu.livefilestore.com...66e.JPG?psid=1

Here's the flip side of the rack, showing the fans on the heatsinks. This will be facing away from the water surface. I threaded the heatsinks to allow use of stainless bolts for fastening. Tried 6-32, but one didn't hold, so went with 8-32 here as well. Mounted the heatsinks diagonally since this provides the best clearance for the fans to do their job of cooling. They're plenty secure with two 8-32 ss bolts.

https://public.blu.livefilestore.com...70e.JPG?psid=1

Spacing from center of one heatsink to the next is approx. 6 & 1/2 inches. This will allow installation of at least 6 arrays equally spaced along the 4 foot rail. I'll start with that, or maybe 5, & see how that goes. The thing I like about using this material & fastening with bolts, is that if I need to modify the set up, it's as simple as drilling additional holes. Electrical hookup should also be easy to modify, with a minimum of soldering. Also still thinking I might add a few MR16 bulbs to the rail as needed. This will allow me to spotlight a certain coral or area of live rock with a custom LED colour of whatever works for that area. Just need to figure out a way to fasten the MR16 bulb socket to the rail. Shouldn't be too difficult.

I'm thinking 3 of these rails for my 4 foot tank. One down the center & two along the outside. Not quite sure whether I'll hang them or make up something to set them on the tank rim. Either way, I plan to install the outside rails so that they can be swiveled to point slightly inwards. A single bolt through the end brackets with a wing nut to allow friction fit with quick adjustment should do the trick.

Looking good so far. Anxious to see how this turns out.

A little more progress on the project since the 12VDC 240Watt power supply & 10 additional heatsinks finally arrived yesterday. Still waiting for 10 10Watt 10,000K LED chips. Chuckle, all those 10s make my eyes go buggy.

Power Supply. Adjustable from 10.07 to 13.58 VDC with the variable resistor. I will probably set it at close to 12 VDC & use separate variable resistors or drivers on each output line to control current & brightness of LEDs. With a potentiometer on each output line, I'll be able to control 3 colours of LEDs individually. This is pretty much mandatory, since different colours of these LED arrays tend to have slightly different maximum voltages, anywhere from 9 to 12. For example, the Royal Blues' rated forward voltage is 9-10 volts, so running them at 12 will sure as hell make them brighter, but I reckon they wouldn't last too long.

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I've now mounted 6 heatsinks on to the first rail with 3 each of the cool white 6,000-7,000K LEDs & 452-455NM Royal Blues. The LED chips are only held on with heatsink compound at the moment. I'll see how secure that is once the compound cures & may leave it at that instead of securing additionally with screws. The tiny screws required are hard to source.

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Original idea was 3 of these rails, but having assembled the one, I think I may reconfigure to have 2 rails only, but with 8 LEDs per rail vice 6. My 77 gal is just under 16 inches inside dimension front to back & 3 rails would be too much hardware with these 10 Watt arrays.

Now it's wait for the remaining LEDs, shop for additional hardware - potentiometers & wiring for hookup. Have a couple more heatsinks on hand, so I can get to work building the second rail.

Great build, following along.
I have been wanting to build one as well, still just learning.
Where are you getting all the components, if you don't mind me asking.
Thanks

LEDs, heatsinks, power supply are all from Asia, via the well known online auction site. Need to plan ahead & be patient, look for deals, be careful of shipping scenarios. Hardware, aluminum etc. I'm trying to get local as much as possible. So far Princess Auto has been the most cost effective for aluminum stock in the sizes I need. Think I'll visit Circuit City today to see what they might have in wire & potentiometers. PA can be a good source for those things as well, but I'm not driving to Kelowna today.

Another bit of work completed, not without hiccups & second thoughts. But I did mention earlier that I'm building on the fly without extensive planning on paper...

Still awaiting the arrival of the 10,000K LEDs, but have wired up 3 each of the Cool White & Royal Blues to the first rail for some testing. Sourcing small screws/bolts to fasten the 10watt LEDs to the heatsinks was an issue, but the other day it dawned on me to check the local hobby shops & scored some M2 nylon bolts plus tap to thread the heatsinks for LED mounting! Worked like a charm until I snapped the tap on or about the 5th heatsink, so I need to get another. Two of the heatsinks I had already tapped for #4 (American std) screws, so I still need to get my hands on some of those.

I decided to snip off the little connectors on the heatsink fans & solder them to the + - terminals of the the LEDs along with the hookup wire. Trying to keep the number of connections to a minimum, but it does have drawbacks, since now the fans are destined to run at whatever voltage is delivered to each individual LED array, vice running at their full 12 VDC rating. I lose the ability to independently control the fans on the heatsinks. Hoping that won't be a big issue, since they may not need to run at full power if the LEDs are not being driven at max current either. Was originally going to use 18 guage wire for LED hookup, but decided on 20 guage single strand instead. This made it easier to solder both the LED hookup wire & the very tiny fan wires to the LED terminals. #18 would have been a very tight fit in the terminal hole. Also added a small section of heatshrink tubing over each connection for protection from the elements... salt water.

Photo is not great, but you should be able to see the relevant details here. The center LED is placed between the two mounted ones for reference, showing the fan connector still on it, whereas the mounted ones have been cut off & wires soldered to LED terminals. Heatshrink tubing on the RH cool white LED has been given the shrink treatment, while the RB LED on the left has the tubing pulled back to show the solder joints. Note also that the cool white LED on the right has no mounting screws yet, this is where I need the #4 screws. The RBs are fastened with the nylon M2 screws.

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A full length shot of the rail. May still modify the hookup wiring to shorten all leads & use terminals to connect the 20 guage wire to larger guage for the run to the power supply.

https://public.blu.livefilestore.com...81e.JPG?psid=1

After soldering the 6 LEDs yesterday evening, I tested each one for current draw with the power supply adjusted to the lowest possible setting of 10.7VDC. This is slightly higher than the rated voltage for the Royal Blues but within the acceptable range for the Cool Whites. Found that the RBs were running at over the 900mA rating, in fact a good bit over 1 amp, so didn't leave them on very long. Fans worked well on all the LEDs. I did hook them all up shortly after lights out on the aquarium to see how it looked & was quite impressed. Great fluorescence on my LPS & amazing shimmer.

I know I'm going to need some sort of additional regulation to limit the current to the RBs in particular, so today I dug up an old 2 ohm variable resistor I've had laying around for decades. Did a lot of reading on various regulation scenarios, voltage, current, pwm, simple resistor & even found out about another possibility, something called a PTC resettable fuse. This device acts a little like a resistor, but the main purpose is to regulate current. If the current rises above the PTCs rating, the PTC will heat up & cut the current, thereby protecting the circuit or LED in this case from frying due to overcurrent. However, since my power supply is relatively stable at the set voltage, it seems that a 2 to 3 ohm (or variable resistor in that range) in series with each LED will be the simplest, most cost effective solution.

Testing of each LED today with the variable resistor set @ 2.8 ohms & power supply @ 10.7 VDC showed a variance from 700 to 740mA for the 3 Cool White LEDs. The 3 Royal Blues ranged from 880 to 910mA with the same voltage/resistance values. This testing also showed the value of proper heatsinking & having the LEDs firmly mounted with heatsink compound. The Cool White LED which I have no screws for at the moment had lifted from the heatsink without me noticing & when I hooked it up the current was rising steadily as time passed. I had been tilting the rail away from me to avoid getting blinded, but noticing the rising current, I snuck a peek & noticed the problem immediately. Once I pressed the LED back onto the heatsink with the compound more or less holding it in place, the current settled rock solid @ 700mA. I ran each LED for a good few minutes to ensure the reading was stable. The fans & heatsinks appear to be doing their job very well. I could even feel some of the heat being transmitted to the mounting rail. Will likely add some heatsink compound to that interface as well to aid further in cooling.

So far the results are very encouraging. The rail is ultra light. I think I will probably end up going with 10 LED arrays per rail. This will provide plenty of options as far as colour mixing goes. Downside is, I still need to figure out a dimming solution. Will certainly not be sophisticated but my current set up has nothing, so chances are my livestock will not care a whole lot. I reckon simply putting the RBs & some blues on first & last using timers will provide enough of a dawn dusk effect & keep things simple. It's kind of what I do now with my T5 & halides, so business as usual, probably a tad better.

Here's a photo during testing, one of the RBs fired up, running exactly at it's rated 900mA current with 10.7VDC applied through the variable resistor set at 2.8 ohms.

https://public.blu.livefilestore.com...88e.JPG?psid=1

Mike looking great i love the mixture BEER and LIGHTS :lol:

Ha, ha, thanks. My homebrew goes good with DIY. I'm reminded of an old Frank Zappa tune, T*tt*es & Beer!

Short blurb to keep the thread going. The 10,000K LEDs have started trickling in thru the mail, but project is stalled since I snapped the M2 tap I was using to thread holes into the heatsinks. Can't get another locally, so not sure this will be solved short term. I have BC Fasteners & Tools bringing in some #4 stainless screws by this Friday, so maybe I can use those to mount the LEDs to the heatsinks. #4 taps are easier to get locally than the metric M2, just not sure the heads on the #4s will be small enough. The fans on the heatsinks are actually attached with what appear to be self tapping countersunk screws, so that may be another option, but again, they're so tiny that they'll be just as difficult to source locally.

Lesson learned, use the proper lubricant for aluminum when attempting to thread with a tap. I was tapping dry.

I had a different approach, I used a CPU heat sink. It can handle four 10w led no problem. For this fixture I used a 30w 900mA and a 10w 900mA driver, both of them 85-240VAC supply.

I like that approach, pretty slick! So if I'm not mistaken you have 4 of the 10 watt LEDs mounted to one CPU heatsink & you've wired 3 in series & one independently? What's the colour combination, I see one blue or royal blue? The housing looks like a PVC coupling & not using any optics? And what about the nifty little swivel mount? What kind of screws are those securing the LEDs?

Please feel free to elaborate on the construction of your LED cannon! More details on the parts & how it's working for you. Don't worry about hijacking this thread, I'd like to see more ideas from people using these 10 watt or even larger LED arrays. I think everyone will benefit.

Very promising looking build so far. It's nice to see someone veer off the beaten path as almost all LED builds I've seen have been done with the 3 watt chipsets on a huge heatsink.

Which website did you order the LEDs, heatsinks and power supply from if you don't mind me asking? Looking to possibly do a LED build for a planted discus tank and this may be a better option than going with 3 watt LEDs as I had originally planned.

Guess it's time to end the vague reference to a certain auction site as the source of my parts. All the LED arrays, heatsinks & power supply were purchased via eBay.

I used one 20000k, one 6500k, one 455nm (royal blue) and one470nm (blue). I used 100 mm (4") PVC pipe and yes I did use optics, one 100 mm diameter glass lens f=80mm. I like it better than individual optics. All the bolts used are 6-32. The swivel mounting was supposed to be used for mounting speakers on the wall. I bought that from Walmart 5-6 years ago. I don't remember what I paid for, but it wasn't expensive.

Thanks for the details. The swivel mount is definitely a nice touch. That's quite a mix of colour temperatures in one LED cannon too! I'm beginning to wonder if my approach will blend the colours adequately.

Progress with my build. BC Fasteners & Tools in Vernon was able to get in some #4-40 stainless machine screws allowing me to mount up more LEDs. I've asked them to bring in another 40 of them plus 2 M2 taps. Not able to use the same holes for mounting as with the M2 nylon screws, but it works. The#4 screws butt up against the curves at the corners of the LED base & the larger head clamps down nicely on it. The #4 tap is larger & more robust than the M2. This time though, I dipped the tap into some diesel fuel to make cutting easier. Diesel is the closest thing I had on hand to kerosene, which is apparently the preferred tap lube for aluminum. Here's a photo showing two arrays, one mounted with the nylon M2 screws & one with the stainless #4s. Several LEDs are mounted using both since I wasn't able to extract the broken pieces of the M2 tap out of the holes.

https://public.blu.livefilestore.com...91e.JPG?psid=1

I've reconfigured the rail to hold 9 LEDs in total. The plan is to start with 5 of the 10,000K LEDs & 4 of the Royal Blue LEDs. Would like additional colours, just not sure how to fit them in at the moment. Perhaps a third rail or some MR16 bulbs. Spacing between the LEDs is now at 4 & 1/2 inches on center. This leaves about 6 inches from the center of the first & last LEDs to the ends of the rail. Two rails to start with, so a total of 19 LEDs for almost 200 watts. The 250 watt power supply will handle that with a few watts to spare. Hoping this will adequately replace my current ghetto DIY 2xT5/2x250 watt Halide rig. Total wattage there is close to 600 watts, I'm overdriving the 4 foot T5 tubes. The 10,000K T5s run morning & evening, with the 14,000K Plusrite Halides coming on in sequence during the midday period. BTAs, LPS, softies & a couple of SPS frags all looking healthy & showing steady growth under the current lighting scheme. Still need to figure out how I'm going to time the LEDs.

Things will be a lot more open with two rails of LEDs replacing this monstrosity.

https://public.blu.livefilestore.com...66a.JPG?psid=1

Have to wait until I hang the rail to see how the LED spacing works as far as blending the 10,000K & Royal Blues without optics. Specs for these LEDs generally quote a viewing angle between 120 & 140 degrees. Intensity will surely be less at the perimeter as directly underneath each array. Will be a matter of adjusting height & spacing between rails to see what works. Further reconfiguration/adjustment is always an option. Still need to complete wiring, measure current for each LED to determine what I need resistance wise for each to run them at the proper level. 5 more heatsinks in the mail & I'll need a few more to get the 9 per rail that I'm shooting for. Couple of spares are probably a good thing too.

How the light is gonna blend is a matter of optics used. You might want to bring them closer and install a few more LEDs.
I did play with some small heatsinks, similar with yours. They need 12V to stay cool and at 12V they are a kind of noisy. If you want to see those contraptions I can take some pics.

A build thread on your light would probably generate a fair bit of interest. More info on your optics & where you got the lens would be useful. How is the lens attached? Do you have more of these lights or just the one & what area are you lighting up with it, tank size etc.?

I'd like to try the rail in the current configuration without optics and see how the colours blend. Looking at the photos of SeaHorse Fanatic's build, the light seems to blend quite well. Unfortunately, other than the number/type of LEDs & PAR readings, details of his build are scant & I have no idea how his LEDs are spaced or if he's using optics. The optics I have for these at the moment are thick glass & quite heavy. Not sure how I would mount them so I'll play with height of the rail above water to see how that works first. I recall reading that any optic, glass or acrylic is going to filter out a certain amount of light. So it's a bit of a trade off between the need to focus & the desire to get maximum lumens out of each LED without filtering.

Not sure what heatsinks you played with, but the ones I have are designed specifically for these LEDs. Running the fans at a lower speed with lower voltage may well shorten the life of the LEDs. If I find the heatsinks get too hot, I may have to cut the fan leads & run them separately at full 12 volts. I only ran each fan briefly to make sure they all work & didn't find them that noisy, barely audible actually. Currently I have fans cooling the ends of my overdriven T5 tubes & I can definetely hear them. I've lived with that sound for years now, so the LED fans will not make a difference in that regard.

Thanks for the continued input regarding your experience with the 10 watt LEDs. And yes, more photos would be cool.

The heatsinks you have are videocard sinks and they sell around $2-3 on e-bay. In one of the first pics you posted they even had the plastic clips used to fasten them to the pc board. If you bought them as specifically designed for led you probably overpaid. When you run just one the noise is not a big issue, but when you run 12-24 that's a different story. When I played with the VGA heatsinks I used same kind of glass lens that you use and I liked them. I don't want to hijack your thread, but I'll post some pics showing the lens mounting.

Here are the pics of the optic system used with VGA heatsinks. 1.5" ABS coupling, 2 rings cut out of a 1.5" ABS pipe, one 44mm glass lens and two #4 screws (stainless) to attach the heatsink to the optics.

Thanks for the pics, good info. Price I paid for the heatsinks is about what you paid as well, I don't think I've overpaid. Good to know what else they are used for. I assumed they were specifically designed for the 10 watt LEDs since the eBay sellers I've purchased the LEDs from often list the heatsinks as well and the item description says they're designed for them. I reckon in the interest of economy in manufacturing, many heatsinks are used for different applications, provided the specs meet the required cooling capability and have the necessary footprint & mounting options.

Not much in the way of progress with the build, but I have been scoring a few more parts that I need. While in Kelowna the other day getting more wire at Princess Auto, I found out about a great electronics outlet not far from there, Interior Electronics. Eureka, a shop full of resistors, capacitors, voltage regulators, hard to find connectors, it was like being in a candy store as a kid. I picked up a few 5watt & 2 watt resistors ranging from 1.5 to 3.3 ohms and a breadboard. This will allow me to run each LED chip with the different resistances to determine what value of resistor I'll need to limit the current to the rated spec. Might be a tedious process & I'll need a resistor in series with the power supply for each LED. Also not the most elegant solution by today's standards with LEDs, but simple & effective. A good thing about doing it this way is that failure of one resistor isn't going to take out any other LEDs. About the only thing that will take out multiple LEDs would be an overvoltage fault of the 12 VDC power supply & I'm banking on that being very unlikely.

I used the breadboard with resistors yesterday to run 2 whites & 3 blues at once. Worked very well & the fans were nowhere near as audible as the four I'm using on my overdriven T5 tubes. In theory the 5 LEDs should have been using 50 watts, but if I recall correctly the wattmeter was showing less than that, so I assume they were being underdriven. Still very bright though & I think the 4 & 1/2 inch spacing between them should work fine without optics if I hang them at the proper height.

For the benefit of those wondering what the H a breadboard has to do with electronics....

https://public.blu.livefilestore.com...93e.JPG?psid=1

Interior Electronics also had some fine little project boxes. What I'm thinking of doing is mounting several of these on each rail with a terminal block & resistors inside to keep things tidy & relatively moisture proof.

I skimmed through this tread a little fast excuse me if this question already have an answer:biggrin:
As I am planning to do a 20W led setup for a couple of my tanks similar to what you are doing but 1st I would like to know how good are these fans at keeping these LED cool as I am planing on running then at full power.
By the way good thread on this build.

Very informative read. I am in the process of trying to figure out how to do a build myself, following along this thread to see how it is done.

Here is a list of parts I am thinking of using:

Dimmer. ( may have a few to run different led temps, blue, daylight 12000k etc...)
http://www.dealextreme.com/p/dimming...s-dc-12v-73618

Daylight 12000k
http://www.dealextreme.com/p/t10-sv8...-dc-12v-112583

Blue light
http://www.dealextreme.com/p/10w-180...r-9-11v-100875
OR
http://www.dealextreme.com/p/31-44mm...-dc-12v-100622

Power supply ( once again a few to run different lights on timer. Not sure if this will work or if I need an actually LED driver supply. )
http://www.dealextreme.com/p/120w-un...-240v-ac-37110

or if I need a proper led driver
http://s.dealextreme.com/search/led%20driver%2012v

any suggestions?

Sorry for the delay in answering your question, I've just returned from a week long backcountry ski trip!

The fans in combination with the heatsink do a great job of cooling the 10 watt arrays since they are more or less designed for them. There are alternative options without fans in the form of larger heatsinks, but I'd like to keep the aluminum mass to a minimum. If you do any searching on eBay for similar items, you will find plenty of sellers offering heatsinks with fans suited for the larger 20 watt LED arrays, as well as the big honking 50, 100 & even larger ones. Needless to say, as you go higher with the wattage, the corresponding heatsink & fan will also have to be much larger to cool the LEDs.

The fans on the heatsink for my 10 watt arrays are designed to run at full speed with 12 Volts DC. I decided to wire the fan leads to the LEDs so that my fans will run at a lower speed, since the LEDs will be run at anywhere from 9 to 10 Volts DC, depending on the size of resistor I put in series with each LED array. I've done some initial short runs to test the rail & it looks like this approach will be fine. If I need more cooling, I may simply add another piece of angle aluminum facing up to give the assembly additional mass for drawing away heat.

The dimmer is something I've also been looking at to control the current my 12 Volt power supply delivers to the LEDs.

The daylight 12000K 5630 SMD LEDs are generally considered insufficient for our purposes, since the LEDs are not large enough to penetrate the water properly. Yes, there are 32 of them on the board for 16 watts, but I'd still advise against trying to use these since they just don't have enough punch per individual LED. About the only advantage to them is that since they're designed to replace automobile lighting, any 12 Volt DC power supply may be used to run them, no driver to worry about.

Your first link for the blue light is the same 10 watt LED form factor that I'm using in different colour temperatures. You will need either large heatsinks, or the fan/heatsink combination I'm using for my build. You will also need either individual drivers for each 10 watt LED, or a power supply in the 12 Volt DC range of sufficient rating to run multiple 10 watters in addition to a current limiting resistor for each 10 watt LED.
The second link for blue light is again, a board with low wattage 5050 SMD LEDs really unsuitable for anything except maybe a night light.

With respect to power supplies/drivers, the preceding paragraph should pretty much answer that. Your choice really. You can either get a separate driver for each 10 watt LED, or a larger 12 Volt DC power supply to drive a bunch of them with current limiting resistors for each 10 watt LED. If you decide to use the SMD LEDs for sunrise/sunset or night lighting, all you need is the 12 Volt DC power supply on a timer.

led build
 

I would love to do a build like yours or Grizzs using leds from Modular Led but just cannot justify the cost a.t.m . I am trying to go cheap and thought going 12v would simplify things. My tank is only 18" deep so was hoping to get away with it...well maybe I should stop being cheap and use proven led's from Modular.

If you wish to pursue the 12 V simple approach, you might want to look into the MR16 bulb form factor. They are designed to run off 12 VDC, even 12 VAC in some cases. Driver built into LED bulb, plug & play, sort of. Price is coming down on these bulbs & I understand there's a company about to launch more efficient/powerful MR16 LED bulbs. Initial customer base will be commercial, but shouldn't be long until they target the domestic consumer.

It's slowly getting to the point where it's more difficult to realize significant savings in a DIY LED build as long as you're not looking for all the bells & whistles such as an EcoTech Radion.

Below are some MR16 bulb pics. This bulb has four 1 watt LEDs in it & pretty good optics. You can even unscrew the bezel & remove the optics if you wish. This would expose the individual LEDs & provide more spread, but also expose them to water spray. They are very bright. Before embarking on the 10 watt LED chip build, I was seriously considering this option. I may still use some of them as supplemental lighting or to spotlight a particular coral/area of the tank. Of course if you have primarily low light corals etc. in your tank, those car lights might be enough, but I wouldn't count on it. For a FOWLR they'd probably be ok.

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https://public.blu.livefilestore.com...94e.JPG?psid=1 https://public.blu.livefilestore.com...98e.JPG?psid=1

Been a while, lots of skiing so not much work on the LED project, but I did manage to get a little more done. I've decided to go with a third rail down the center. Probably have some funky coloured night lights & one or two day supplement arrays on that. Maybe even a green or red. The two outer rails will do the bulk of the work. I've cobbled them together using two pieces of plywood to experiment with spacing & get an idea of what kind of spread the currently planned mix of LEDs will give.

I've ordered 10 more heatsinks with fans & 10 Blue arrays to see how they will work with the current bunch of Royal Blues & 10,000K. Still need a bunch of 5 to 10 watt resistors in the 1.5 to 3.3 ohm range to tune each LED array to the proper running voltage/current. As it sits right now with 17 LEDs, heatsinks, aluminum & plywood, the unit weighs in at 1.8 Kg, that's 4 lbs. Nice & light. Current plan will be to have 9 LED arrays on the two outer rails & maybe 4 to 6 on the center rail. Also need to add the weight of resistors, more wire, project boxes to wire the whole shebang etc. Might also add some plywood skirting to make some sort of open hood in order to minimize light spill & hide the aluminum. With any luck I'll be able to keep it under 10 lbs.

Here it is. Spacing between LEDs on each rail will be approx 4.5 inches. Spacing of LEDs between rails is around 5 inches. I plan to rotate the outer rails slightly inwards. No optics, I'll play with height above water to find a good compromise between spread & light output.

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End view. The plywood will allow me to drill holes easily & reposition the rails if necessary. The wingnuts provide quick adjustment of the inward tilt of the outer rails.

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Another view to better illustrate the tilt on the outer rails.

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Any new developments on this Mike?

Well, sort of. Still waiting for more heatsink/fans as well as Blue LEDs as per my previous post. Somewhat rethinking the resistor method of controlling current to each LED so I've also ordered ten 12VDC constant current drivers to see how that will work. It may be more efficient than resistors but the downside is, they are somewhat larger than a 5 or 10 watt resistor & they also cost a bit more. These constant current drivers will accept an input of 12 to 24VDC and provide constant current of 800-1000mA at 8-12VDC out. As with the resistors, the plan is to use one per LED.

One idea I considered was to use 3 low resistance, high wattage resistors, one on each of the 12VDC power supply outputs feeding 3 different colours of LED. Not that keen on that idea since these resistors are physically quite large & if one goes bad, I risk frying all the LEDs downstream of that. So I'll probably stick with a resistor or driver for each LED. This will provide a safety factor & also allow me to tune each LED individually. However, not finished yet, & I've also ordered three 12VDC, 8A LED strip light brightness controllers. Might use them in combination with the resistor/drivers. I'll open one of these up to see what's inside when they arrive. Curious to see whether it's just a potentiometer or if there's some electronic wizardry going on in there. My 10watt LEDs are bulk ordered & not binned so production variations will require slight differences of current to each LED for the desired light output. I don't have a PAR meter to measure light output, but at least I can tune each LED to draw at or below the rated maximum.

Going shopping this afternoon for either plywood or thin pine planks to build some sort of enclosure to hold the rails. Would like to keep it open, so I'm thinking some wide side pieces as a frame & a few along the top to mount the terminal boards, resistors/drivers as well as keep the wiring neat. I'd really like to keep the weight of the whole thing down.

I've seen a few similar builds now on RC, one where the chap is using the larger 50watt LEDs. The build looks amazing but much more involved than mine since he needs to cool each LED chip with this monster heatsink with liquid cooling & huge fan. Since the higher wattage LEDs generally need higher voltage (36 VDC), your choice in power supplies gets limited & you end up having to buy the ready made drivers for whatever wattage LED you intend to use. One of the things I prefer about my build, is that 12VDC power supplies & drivers are more common. I can also diversify a bit easier with the colour spectrum & if a LED goes bad, I'm not out as many $$s as with the larger ones.

I've been following the build on RC...he's done an amazing job. His light only requires a basic heat sink (VGA, not CPU) but it just looks huge. The Heat pipes don't use liquid...but some others suggested he try liquid cooling. I think that would be too much effort.
I'm not done my cree build yet and I wouldn't change anything right now, but the large multi-chip builds interest me a lot.

Got it together for test firing
 

Still a bit of work ahead, but I now have the components for assembly & testing. The wiring needs some serious cleaning up, but I'm still experimenting with different options to drive the LEDs. The 3 dimmers work very well so I'll order a few more of them for added flexibility in controlling the intensity of each colour. I'm close to their current limit of 8 amps each, so there's a safety factor to consider. The 12VDC constant current drivers I ordered should arrive within a week, so I'll be able to see how they might fit into the scenario.

A summary of the fixture's current config:
-Three rails of nine 10watt LED arrays each for a total of 27 LEDs,
-Two outer rails each have five 10000K White & four 452-455NM Royal Blue,
-Center rail has five 460-470NM Blue & four 6000-7000K White,
-Three 8 amp Dimmers, one controlling all the Whites & one each for the Blues & Royal Blues,
-One heatsink with fan per LED,
-One 250watt 12VDC power supply,
-Terminal boards, wiring, stainless steel hardware & aluminum angle stock,
-Mahogany veneer wood frame (I scored the wood real cheap in the clearance pile at Windsor Plywood).

The fixture weighs just over 12 lbs, or approx 5.5 kg. I ran it last night trying each colour on it's own & in various combos, including full on. Although the calculated wattage with 27 ten watt LEDs is 270 watts (more than the power supply max wattage), the energy monitor showed around 230 watts with all LEDs & fans running. I attribute this to the fact that I didn't run them at their full voltage/current. I dialed the voltage on the power supply down to 9.9 VDC & using each dimmer, further lowered the voltage delivered to each colour to < max rated forward voltage. When time permits, I'll perform current measurements on each LED to confirm they're operating at or below max rating.

One of 3 dimmers I used during the initial test. These are actually sold to dim 12 volt SMD LED strips, but they work fine with the 10 watters, provided you mind the current rating:
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The entire assembly. Wiring will be cleaned up, shortened, more terminal boards added & dimmers mounted remotely near the power supply:
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The 'bright' side:
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Side view showing the Mahogany veneer frame. This should look pretty good with some finish & trimmed with moldings:
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As far as the test run goes, I very much like what I saw last night & don't think I need to modify anything with respect to colour blending & spacing between the LEDs. I used a couple of 2x4s to rest the fixture on the rim of the tank, much closer to the surface than it will eventually hang. Quite anxious to get it completed now & start experimenting with height above water. The Royal Blues in particular bring out a flourescence in my LPS & soft coral that I've never seen with my current MH/T5HO set up.

Some pros & cons having reached this point:

Pros (as I see them anyhow);
-DIY, so I can repair or modify any part of the fixture myself with parts readily available & relatively inexpensive,
-Fewer LEDs required than with the more common 3 watt builds,
-Not as heavy as builds with massive heatsinks,
-10 watt LED forward voltage is in the 9-12 VDC range, more flexibility in choice of drivers, power supplies etc. Easier to adapt to off grid power, solar, wind, battery etc.

Cons;
-DIY, not everyone's cup of tea,
-Noise from fans (didn't seem bad at all during test run),
-Limited controllability compared to the fancier manufactured fixtures, i.e. dimming is manual at this point,
-I have no measurements as far as light output etc, so experimentation & time will be needed to confirm suitability. Manufactured fixtures have all the testing done & data available. My build is a best guess as to what I require.

More to follow as additional components arrive & I finalize assembly. I plan on ordering a couple more power supplies so that I can run each colour on a separate timer to get some form of sunset, sunrise effect. I also need them to keep from overworking the single 250 watt supply. Still pondering whether soldering the heatsink fans directly to the LED contacts is a good idea or whether I should cut the leads & run them at the full 12 volts all the time. Stay tuned.