GU10 LED Build Thread (Chinese Ebay Lights)

[Belac]

Sockets came in

[Nitro Reef]

Today I threw together a simple canopy to hide the bulbs and screws at the top. I'll post pics after I paint everything black.

 

 

[TinyGiant]

I don't get why everyone seems to want to diverge from Tiny's original formula, guess everyone just wants MORE POWER!

 

Anyways, I'm going to go ahead and re-post Tiny's formula since people keep asking:

 

 

lol i stopped responding to those questions.. i put a lot of work into that first post .. got tired of retyping it.

 

 

maybe i'll reorganize the first post and put "GU10 quantity equation- (how many lights to use over your tank)"

 

that seems to be the biggest question.. so maybe i should put it up top so more people see it.

 

 

i just hit my 2year mark this month.

 

Click the Right side of my Signature image and see the latest posts. took a short video and a couple FTS.

[TinyGiant]

Today I threw together a simple canopy to hide the bulbs and screws at the top. I'll post pics after I paint everything black.

 

 

 

 

Looks good.

 

running that much light on the 5g will be pretty intense.. definitely keep your photo period short in the beginning.. The tank i started using these lights on was a 5g. I found most of the corals (especially zoas) grew extremely bright but also became very small.. Polyps didnt need to be large to get the light they need and it seemed they started to grow smaller to make up for the intensity.

 

just pay attention if things dont open or start to bleach out just reduce the photo period.. or raise the lights.. or you can always lower them and take the optics off (blends alot better that way.. just not as intense)

[Nitro Reef]

Thanks TinyGiant. Thanks for this thread, it was a fun build. I have extra bulbs so I think I'll try taking the optics off of them. I never done that before but I'm curious to see if I can do it. I got my stand and hood painted up last night and now I'm ready to get things started.

 

 

[Belac]

Make sure the leds are glued down to the heatsink before you leave the lenses off long term.

[Nitro Reef]

Is there a thread on how to remove the optics from these bulbs and what glue/epoxy to use?

[ChouDawg]

As far as I'm aware the latest bulbs people have been buying, at least from the "luck" seller, do not have the original issue of wobbly board after you remove the lenses. I know from experience after pulling the lenses off and swapping out some of the LEDs the boards are on there well. How you go about getting to the optics might vary from seller to seller but mine has three tiny philips screws and the front metal part comes off with the optics. For glue/epoxy you can put a dab of superglue around the rim of the board or if the board is really loose, lift it up and add thermal epoxy to get the heat transfer and glue effect.

 

Tank is looking great TinyGiant, looks like you were able to restore the tank exactly to the way it was before the arch disaster.

Edited December 22, 2012 by ChouDawg

[Nitro Reef]

Thanks ChouDawg and Belac for the info.

[Belac]

Nitro I ment to tell you earlier that your set up looks great.

[Nitro Reef]

Thanks Belac !

[mcarroll]

I'd like to get opinions on my diy light stand and bulb configuration. I'm setting up a 5g pico reef. I used 1/2 inch pvc to construct the stand. I'll eventually paint it black. I'm using 10 3x1w bulbs in two rows of 5 alternating blue and cool white. I have the bulbs 8 inches above the water. This height seems the best for color blend. The bulbs are 1/2 inch apart. Should I reconfigure the bulb placement and try to get them closer together or do you think the light blend is adequate?

 

 

With bulbs not right next to each other (as in most of the builds here, including the OP) you will not get great blending between colors. Maybe you won't mind.

 

8" is also pretty close for such a shallow tank.

 

At least 12" (as in most builds including the OP) is the recommendation for best effect/least bad side-effects. I've actually had better luck with my lights at about 17". My tank is 19" deep and I have corals at the surface as well as deep in the tank growing on the bottom glass - all are doing well in growth and color at depth, but things still seem too bright at the surface.

 

-Matt

[Nitro Reef]

Thanks Matt. I was going over the spread of the light in my setup yesterday with a sheet of white paper. I did see the light separation at the surface of the tank. I'm going to go over different heights and see what height would be better.

[mcarroll]

Thanks Matt. I was going over the spread of the light in my setup yesterday with a sheet of white paper. I did see the light separation at the surface of the tank. I'm going to go over different heights and see what height would be better.

Water diffracts light much differently than air and reflects as well, so the paper test isn't good for much more than a really rough idea what the lights will do.

 

In short, water will make the color seperations more pronounced due to the wider-angled light being either reflected off the surface or diffracted straighter down into the tank. The light in the water will "be shaped" more like a cylinder vs a (30°) cone as in the air.

 

Fill er up, put in some rock, then judge how you like it.

 

-Matt

[Nitro Reef]

Thanks Matt. Yesterday I re-did my lights. I went with Tiny's formula and went with 7 bulbs in a line and eliminated the space between the bulbs. I'm using 4 blues and 3 cool whites. I'm thinking of getting the 3x1w bulbs with 2 blue and 1 white led's. I also raised my lights to 12 inches above the top of the tank. Good change and nicer blend of color!

[Belac]

No need to order new bulbs if you have a soldering iron. Just move a few of the leds around on the bulbs.

[Nitro Reef]

I might just try that.

[ChouDawg]

Ya I swapped one of my 2B/1W bulbs to 3B and wired that separately so now I have a 19B/8W ratio. I'm very curious to see how my tank would look under a full spectrum setup with some UV/Red/Green thrown in as I feel like I'm missing a bit of the pop but either way very happy with my setup so far.

[neven]

in regards to why i diverged from the original format was because i wanted to mount my fixture higher since i hate moving my light to clean the glass (or rather if the light needed to be moved than my wife would make me do it). I mirrored the information in this thread onto another local forum about my build and i definately stressed the 3x1W or 1x3W bulbs and the formula for bulb numbers due to heat issue stating the only reason i used 3x2W bulbs was because i was using a fan.

 

Another reason i went a bit more was because i plan to get a few bulbs manufactured with a red emitter included and want it blended with the whites and blue as much as possible to avoid spot lighting, As to the other emitters with the red, im leaning towards a blue and coolwhite, but i can choose pure white, yellow, green and warm white aswell. my set up works out to 4 bulbs in place of the 3 bulbs using the formula

[Nitro Reef]

Hey Belac, good suggestion!! I just got done changing some of my led's out of my bulbs. I didn't realize how easy it was! Now all my bulbs have 2 blue and 1 cool white. Really nice color blend too. Makes me wish I didn't just buy a t5ho light setup for my 30g I have waiting to start.

[mcarroll]

Thinking out loud here, I wanna look at this a few ways, so bear with me.

(And someone please correct me if I get this wrong somewhere..I'm neither physicist nor mathematician...LOL)

 

Some groundwork first.

 

Water absorbs light much more than air does. In water, light intensity decreases exponentially in fact. In air, the inverse square law applies...which in a nutshell says you get 1/4 the intensity at double the distance....or if you're going the other way....4x the intensity at half the distance.

 

That's nice info (check those links!), but not necessarily clear. Taking it back to the tank...

 

OK...a specific (and simplified) example that we can play with. 12" of water in tank, LED's 12" off surface of water, 400 lux at the tank bottom.

 

Raising The Light

If we change the light to be 24" off the surface of the water, our lux reading drops to 100.

 

Lowering The Light

What if we halve the distance of the light to 6" off the water surface? Lux climbs to 1600!

 

Increased Water Depth

What if we leave the light at 12" but double the tank depth? Lux drops to 20.

 

Decreased Water Depth

Wanna guess what happens with the light at 12" but with less water in the tank...say 6"? 160,000 lux!

 

You can see that while changing the height of the light makes a difference, it's nowhere near the difference that accompanies a change in the water depth. If your tank is less than 24" deep - and especially if it's 12" or less deep - you're really hitting your tank with a lot greater intensity than TinyGiant's reference standard rig already - with no changes to bulbs or bulb layout. Get it?

 

You've got relatively less water distance (so less attenuation) and more air distance (which has comparatively little effect on intensity).

 

The bottom line: Unless you're running a very deep tank (more than 30" I say), and/or running the lights 24" or more off the tank, there's no reason to run brighter bulbs. Zip. 3w LED's with 30º optics KICK BUTT. And if you want to experiment with more light, the above numbers are very good to keep in mind - don't roast your corals! :-)

 

-Matt

 

P.S. I've read that lensing (collumating) changes the behavior of light when considering the inverse-square law....but I think that since we're looking at lux maybe the lensing is factored out. If I'm wrong, anyone know what the difference would be in the example calculations?

 

P.P.S. Also don't forget that those 30º lenses, in addition to giving your light the shape you want, are basically 4x intensity magnifiers. i.e. 100% of the LED's light is going into 120º of spread by default, but he lens packs that same quantity of photons into 30º of spread giving a 4-fold (aka 400%) increase in intensity....with a little loss (guessing 5-10%) due to the lens's absorption. If light spill isn't a huge concern and raising the lights isn't possible or enough to get the intensity where you need it, 45º or 60º lenses might be very worth experimenting with in lighting of shorter tanks. I have corals growing at the very surface of my tank and I may try out some 90º or 120º lenses.

[ChouDawg]

So I did a bit of simple geometry and discovered with 60º optics I want my fixture at about 11" from bottom of the tank to get a 12"x12" spread, this would of course put the fixture underwater in my 12" cube. The equivalent height for 30º optics is about 22" or 10" above the rim of the glass. My question is, would both 60º optics at 11" and 30º optics at 22" have the same intensity, PAR/Lux throughout the depth of the tank?

 

With my current setup 5" from the tank rim, 17" from the bottom I'm theoretically getting a 20" spread which is a 4" circle of light spillage. The light spillage doesn't bother me but I want to make sure I'm utilizing all the power of my LEDs and not just wasting away 20% of my light over the edges. I have more than enough confidence in my light being more than sufficient to grow just about everything but this is one of those questions that popped into my head and won't go away till I have an answer.

 

On a side note, I messaged "luck" on eBay to see if I can get some red, turquoise and true violet 1W bulbs to do a full spectrum GU10 experiment. After seeing the colors on the full spectrum thread, I now crave that "pop"

 

P.S: Merry Christmas fellow Reefers

[mcarroll]

Chou:

 

Once that light cone hits the water surface it becomes a lot more like a cylinder than a cone, so best to calculate to the water's surface vs through the water at the tank bottom.

 

This link (which should have made it into my post above somehow) should help you visualize what's happening with the light. (Both reflection and refraction..and the effects get more pronounced...less light entering the tank...the wider the angle.)

 

Also, fwiw, there's virtually no light spillage from inside the tank due to the reflectivity of the glass. Spend your energy worrying about spillage over the top...or what you're having for dinner tonight.

 

60º at 10" of height from the water gives about a 12" diameter footprint. After measuring with a LUX meter (which you should get Chou...$15-20 on eBay...I can tell you're nerdy enough to make use of one! ), only about the inside 10" or so of that 12" is really intense (80% of max) and this is roughly what will generate your column of light that more or less fully penetrates the water surface.

 

At only 5" of height from the water surface, that will give you a little less than a 6" diameter spot, with about 5" that's really intense. (And purely due to the reduced distance from 10" to 5" your intensity will be about 4x what it was at 10"! Something to keep in mind!)

 

OTOH, 30º lenses at 10" will give you a little over 5" of spread...and about twice the max intensity of 60º. The column in the tank would be about 4" or so in diameter.

 

Also, considering all factors, 30º lenses will have less loss than wider angles, so they are a bit more efficient...not sure of the significance of that difference, however. I say try what fits your scenario and make adjustments as needed.

 

I hope this helps! Merry Christmas!

 

-Matt

 

P.S. "True violet" (i.e. not the marketing term) is a combo of reds and blues. Are you talking about that or one of the discreet wavelength LED's marketed by several places in our hobby as "true violet" that run below 450nm? (Actinic was a more useful marketing term - see sentence #1.) Likewise, Turquoise is predominantly green with a lot of blue and a little red. While Violets can be good as grow lights for terrestrial plants...not sure I see a lot of point to them in a reef? Double down on that for turquoise. If you're combining colors, those links (check the color coordinates) should at least give you a good idea of what you're combing so you might have an idea of their effects in advance of purchase. :-)

[ChouDawg]

Wow to say I had to read your post more than a few times is an understatement. I have a strong feeling someone else studied engineering. Actually I think a friend of mine has a Lux meter, if it's water proof I may have to borrow it for some nerdiness. It's funny I learned all about light reflection and refraction in school and even did labs on it but none of it came to mind when doing my brainstorming.

 

Thanks for the info on the light diffusion, makes a bit more sense now. i think I'll leave my lights as is, as my corals are all very happy, no one seems to be stretching for light and aside from the bleached out green birdsnest everything else is colored up nicely.

 

As far as the True Violet I was referring to the hobby name for the ~420nm spectrum LEDs. The TV, Turquoise and Red are supposed to help bring out the reds, greens and oranges and hit the photosynthetic spectrum that the RB/CW LEDs don't cover. Most full spectrum setups use RB and Neutral White instead of Cool White so I may see if "luck" has some of these as well. Just got a reply back that Turquoise is not a color he has so I will have to re-do my "full spectrum" ratio.

 

Tbh I haven't fully gathered all the information regarding full spectrum lighting but after some research I WANT! If you haven't taken a look yet, the Full Spectrum LED thread on N-R has all the info you could ever want.

 

http://www.nano-reef.com/topic/294733-full-spectrum-led-tank-pictures/

[Belac]

There are a few sellers selling violets, greens and red lights. I plan on getting one of each to play around with eventually. I am also planning on mixing cool whites and soft whites too.I am going to attemt full spectrum with gu10s