DIY LEDs - The write-up

[der_wille_zur_macht]

Way to tag team.

 

[staggeringwade]

Thanks guys, I almost understand what your saying, but I just haven't gained enough knowledge thus far into electronics yet to really interpret the spec sheets correctly.
I'm so glad you guys are here everyday answering the same questions over and over again to us noobs.
I think I will just leave the drivers as is for now.
I'm going to add a middle bank of leds for better coverage when I can afford to do so. At that point maybe I can whip out the meter and tweak things a bit more.

If any luck at all the nylon washers won't be back ordered and I will have this on my tank by the end of next week with pictures.
I have asked around in the Montana Forums if anybody has a par meter, but nobody has one. Not surprising since I only know 3 reefers in montana? There is finally a very nice reef shop that opened up in Bozeman, I'm persuading him into starting a reef club ASAP and maybe providing the club with a par meter.

 

[TheFishMan65]

I'm so glad you guys are here everyday answering the same questions over and over again to us noobs.

It is not the same questions over and over. It is the same question with lots of variety in the answer

If you can't find the washer shoot me a PM. I think I have extras and can check.

 

[laverda]

I did an experiment for 1 week:
Had all my RB off for 7 days(originally I had a 50/50 split XRE white/XRE RB)
Basically the colonies where under a yellowish light(much like a 10k MH).
When only the XRE whites were up and running.

In 7 days I had browned off and almost killed 3 SPS colonies.
Adding my RB back to the blend, and Ive stabilized 2 of them...not sure if the third will make it.

If you've never done an array before, Im just recommending you use caution and go with the tried and true blends that people are doing. Based on my experiment, my next array will be a 60/40 split RB/W(maybe as high as a 75/25).

To me it seems that the corals seem to like the RB better. I cant confirm fully till I let my corals recover a bit, then I will go exclusively RB for 7 days and see how they take it.

As someone else pointed out the corals should have been fine for a week with reduced lighting. That makes me think they actually do not like the specific white spectrum of your LEDS. Or perhaps the lack of blue with just white causes a problem for them. Interesting either way.

 

[pheinzig]

As someone else pointed out the corals should have been fine for a week with reduced lighting. That makes me think they actually do not like the specific white spectrum of your LEDS. Or perhaps the lack of blue with just white causes a problem for them. Interesting either way.

And someone pointed out that they werent under enough par because the LED's went from 24 to 12.

Who knows.
I personally will do my next array with a higher ratio of blues. And use either MCE's or XPG's

 

[yeldarbj]

I have to say thanks to everyone on this thread for all the valuable information. It took a couple of weeks to work my way through the thread and in the mean time was able to order and assemble my first phase of my LED build. I've been running 6 T5 bulbs for a long time. I initially planned on getting a Reefbrite to replace a couple of T5's (Blue & Actinic bulbs), but decided I could do better building my own - thanks to this thread and several others that are linked on the summary pages.

Since my canopy was custom built (by me) to house the T5's, I decided to go with 34" aluminum channel (1 3/4" x 1" x 1/8"). Thanks to Grim for pointing out Speedy Metals - great service and cut to fit. My initial strip is 12 Cree XR-E Royal Blues with 80 degree optics, powered by a Meanwell LPC-35-700. I spaced the LED's at 3". It's about 7" above the water level. The aluminum channel does get warm to the touch, but not warm enough that I have to pull my hand away from it. I currently don't have any active cooling. I'll probably mount a couple PC fans above the strips, blowing down.

I thought I had butchered my soldering, but it fired up the first time, no problems. I just finished my second strip today. It's got 6 XP-G cool whites and 5 XR-E RB's, also powered by a Meanwell LPC-35-700. It's a very blue mix, but those are the colors of T5's that I was initially replacing. I'm already planning on replacing the back 2 T5's next with closer to a 50/50 mix of color and probably mixing in some neutral whites.

 

[JohnsonSBK]

Hi everyone,

hoping into the DIY LED world after looking around a little bit. looking to cut my energy bill down so i dont have to use my 2 400w halides. just looking through as quickly as i have a few red flags have caught my eye.

the big one was that people have talked about how not much is known about how well hard corals do under LEDs long term 2+ years. would it be worth while to put 2 T5s on it to help with color?

another problem is i have a 48x30 tank so finding a heat sink that would fit the tank front to back and side to side is very difficult and expensive. is there any reason why i couldnt use a piece of sheet AL and have a lot of fans to cool it?

and lastly how many drivers i would need to run 100+ LEDs seems like a i think i remember i would need something like 10 drivers?

any thoughts would be very appriciated

 

[sammy113]

Hi everyone,

hoping into the DIY LED world after looking around a little bit. looking to cut my energy bill down so i dont have to use my 2 400w halides. just looking through as quickly as i have a few red flags have caught my eye.

the big one was that people have talked about how not much is known about how well hard corals do under LEDs long term 2+ years. would it be worth while to put 2 T5s on it to help with color?

another problem is i have a 48x30 tank so finding a heat sink that would fit the tank front to back and side to side is very difficult and expensive. is there any reason why i couldnt use a piece of sheet AL and have a lot of fans to cool it?

and lastly how many drivers i would need to run 100+ LEDs seems like a i think i remember i would need something like 10 drivers?

any thoughts would be very appriciated

You don't really need to cover the entire footprint of the tank with heatsinks. What I've done in wide tanks is to use multiple heatsinks and you can have a gap between them. Lets say you can do 4 heatsinks profile 7.4" x 22" and mount them front to back leaving 4" on each end. Spacing between heatsinks will be around ~3.5". That will cover just fine your tank but can certainly be achieved with smaller heatsinks than that.

Just wanted to give the idea of using the heatsinks looking to the front instead of running left to right.

For drivers, Meanwells run 13~14 LEDs each. You can also look into series parallel connections and there are some drivers that runs a big string of LEDs

 

[JohnsonSBK]

well call me cheap but even doing the heatsinks that way im still looking at 4 pieces so thats about $200 total. is a heatsink really going to make a huge difference compared to pieces of sheetmetal with fans cooling them?

 

[jusmee]

The difference is that with commercially made heatsinks, you get a measured/specified thermal resistance. With a home made heatsink, you are guessing. If you run the LEDs too hot, they will not last as long, and might even fail outright. Could be expensive. So you need to overestimate what will be required for the homemade system (unless you devise some tests to figure it out).

As for cost, with good heatsinks, you might be able to avoid using fans, so that's a bit of saving to offset the cost.

 

[peterbrescia]

Hi there, I finally finished my project, something I would never been able to accomplish without you guys and this website. I now know how to soder and work with LED lights, can't weait for my next project (a new 50 gal sump).
Here's a link to my thread with lots of step by step pix.

http://www.reefcentral.com/forums/showthread.php?t=1894951

I used locklite gel glue from home depot to attach the lends, I attached the lens to the nilon washer not to the star, just in case I need to remove the lens for some reason preventing me from braking the led.
I used 18-7 (7awg wires wraped up into 1 cord) to connect the leds to the remote dimmers and drives. I found out they also make 18-10 but home dipot did not have it in stock.

 

[wld1783]

I would not do that. It often causes more problems than it prevents. It reduces the all important cooling of the LED's dome. It can make future repairs a disaster. You are supposed to be protecting your fixture/LEDs from direct water contact anyway, and since the fixture is the warmest thing around you should have no condensation issue at all.

kcress

I'm just catching up on the thread and wondering what problems you had using the led seal. Or problems you know of using this. After talking to LuxDrive I decided to use it on a fixture in my sump room which has high humidity. So far I really like it. It seems to seal perfectly while allowing optics to snap on.

I was most worried about splash and long term corrosion. A pump, a fish, myself or humidity. I've replaced a few MH bulbs that cracked for the same thing. The last one was a clam that closed up quick when I moved a fallen coral.

BTW you should see my 5 year old T5 fixture, it has corrosion all over and has never been splashed as far as I know also my dehumidifier has a bit of rust on it and it runs hot even in the winter.

As far as heat my heatsink from HeatsinkUSA is between 85-91 Degrees F depending on room temp. I really cant see how snap on optics would be much different than a thin coat of polymer. Plus I thought heat generally rises. At least in gasses and liquids.

Just my 2 cents but would really like to hear from someone who has used it and would recommend against using it because I plan on coating all my fixtures with it.

 

[wld1783]

I have to say thanks to everyone on this thread for all the valuable information. It took a couple of weeks to work my way through the thread and in the mean time was able to order and assemble my first phase of my LED build. I've been running 6 T5 bulbs for a long time. I initially planned on getting a Reefbrite to replace a couple of T5's (Blue & Actinic bulbs), but decided I could do better building my own - thanks to this thread and several others that are linked on the summary pages.

Since my canopy was custom built (by me) to house the T5's, I decided to go with 34" aluminum channel (1 3/4" x 1" x 1/8"). Thanks to Grim for pointing out Speedy Metals - great service and cut to fit. My initial strip is 12 Cree XR-E Royal Blues with 80 degree optics, powered by a Meanwell LPC-35-700. I spaced the LED's at 3". It's about 7" above the water level. The aluminum channel does get warm to the touch, but not warm enough that I have to pull my hand away from it. I currently don't have any active cooling. I'll probably mount a couple PC fans above the strips, blowing down.

I thought I had butchered my soldering, but it fired up the first time, no problems. I just finished my second strip today. It's got 6 XP-G cool whites and 5 XR-E RB's, also powered by a Meanwell LPC-35-700. It's a very blue mix, but those are the colors of T5's that I was initially replacing. I'm already planning on replacing the back 2 T5's next with closer to a 50/50 mix of color and probably mixing in some neutral whites.

Just remember to keep the LEDs cool. If your AL3 C tube is too hot to hold tight its too hot and needs more airflow. I've even seen it doubled up for more surface area.

 

[kcress]

JohnsonSBK; Heatsinks? The thread immediately above your post has cheap aluminum U channel used very effectively. ??

 

[mak3mydae]

I have dimable buck pucks that drive to 1amp (not sure of the model, sorry) and i took off the potentiometer and i tested how many ohms it has. It read about 5k ohms. I want to switch it up to a sliding potentiometer. The one i have is 10k ohms so if i were to put that on the buck puck, i would only be able to use half of the potentiometer before it shut off. I want to be able to use all of it, so i put it in parallel with a 10k resister to try to bring it down to 5k. while i was able to use the entire potentiometer, the dimming wasnt linear. After about 1/10 of it, the LED was pretty much at maximum brightness. Is there anything i can do with the potentiometer i have now? Or do I have to do a bit of shopping to look for a 5k one? (Sorry if some of this didnt make sense. My brother was trying to explain what he was doing)

Anther question, I have a rimless tank, so I dont have a canopy and i dont want to rest a fixture right on to the tank. What kinds of housing and mounting do you guys use? The tank is 24x12 so its not super big.

TIA

 

[kcress]

kcress

I'm just catching up on the thread and wondering what problems you had using the led seal.

Hi wld.

I have not had any problems with "LED SEAL" because I have not and never will spray any electronics I need to service or care about, with a mystery spray relabeled by an LED retailer.

I have had to throw away thousands of dollars worth of electronics that had fixable problems that were un-fixable because they'd been "protected". Customers occasionally demand coatings. Sometimes justified, but most of the time for a false sense of security, or "for good measure".

Needing a Spray for a fixture you've made to mount over the top of an aquarium is akin to declaring that you've done an inadequate job of building your fixture. There is no reason; short of inadequate ventilation, sorry protection, and bad or no planning, to need to resort to magic spray.

This LED Spray is like duct tape. It's not needed unless it's a Rube Goldberg situation. And to carry on the duct tape analogy, have you tried removing duct tape that's been in the sun for a few weeks?

That spray could be just as troublesome...

If you're building a military communications radio that has to go from desert, to mountain top, to sea, to the cargo bay of a plane, and into a steaming jungle, then you need to conformal coat your electronics and recognize that you likely will never be able to repair that radio but just s**t-can it when there is a problem. This is because there is essentially no control over the atmosphere around that radio.

If we are talking about a fixture over a tank there is no valid reason to have large concentrations of condensing moisture surrounding your electronics. You can do better than that.

Your fixture's function will decay rapidly if any direct moisture can ever reach your LEDs or their connections. Your clam is an example why you must always provide direct protection. My fish occasionally get spooked while at the surface. Their panicked dives leave rivulets of water running down the living room walls.

I don't know how else to coach you to not take the low(wet) path in life but to take the high dry path.

 

[wld1783]

kcress

You make a valid point about repair but just like thermal adhesive a wire brush takes it right off the heatsink. Personally I like to build my projects to mil-spec and feel electronics in a marine environment do need some added layer of protection.

I feel that LuxDrive would not put their name on it nor recommend it if it is simply some "mystery or magic spray" Considering its less than 20 bucks I doubt there is a lot of profit in them promoting it. Having several thousand dollars in LEDs it might be worth the little extra it costs. I was really hoping someone who actually used it as I have would give a qualified opinion of it...Positive or negative. So far I still have a positive opinion of it. Its been well over a month since I coated one of fixtures and have yet to see any negative effects.

 

[yeldarbj]

Just remember to keep the LEDs cool. If your AL3 C tube is too hot to hold tight its too hot and needs more airflow. I've even seen it doubled up for more surface area.

JohnsonSBK; Heatsinks? The thread immediately above your post has cheap aluminum U channel used very effectively. ??

The aluminum channel tube gets warm to the touch, but I don't have to pull my hand away while holding it. Toward the end of the strip, it gets some airflow from a 90mm PC fan (used for cooling the T5's). In that area the aluminum is barely above room temp so I'm going to mount another PC fan above the tubing to blow down on it. I think it will be plenty of cooling.

The channel tubing works great and is cheap. Granted, my LED's are spaced 3" apart and in a single row. I could definitely see the need for a full heat sink when high numbers of LED's are packed closely together in multiple rows like many of the builds.

I'm wondering if I could even get by with using 2" x 1/8" or 3/16" flat aluminum, especially with the use of fans.

 

[TheFishMan65]

wid, Thr brush take it off the heat sink, what about solder? Have you tried replacing and LED? I think that is the real question.

 

[jusmee]

wid, Thr brush take it off the heat sink, what about solder? Have you tried replacing and LED? I think that is the real question.

Use the right stuff and there's no problem. It is solder thru lacquer. I will be using it on mine.

http://www.jaycar.com.au/productView.asp?ID=NA1002&keywords=spray&form=KEYWORD