DIY LEDs - The write-up

[der_wille_zur_macht]

Der - As for the XP Royal blues. Why do people not use these? Only because the pricing is higher than the XR's for the same performance? Only difference is the viewing angel?

-Dave

Probably habit and availability. Some of the smaller retailers only stock the XR-E.

Hi guys, what would you recommend for a 96"x8"x8" ? Low-medium light corals only: GSP, ricordia, zoas.

Interesting tank dimensions! That like, what, 28 gallons or so? You'll need more LEDs than a conventional tank that size because your space is so distributed.

You might want to do two "strips" of aluminum channel or L for heatsinks. You could put 24 LEDs on each strip, spaced such that they're staggered (if that makes sense).

Hey if I wanted to run say 4-6 xpg whites over my fuge would I use the meanwell eln 30-24 or the eln 60-24

Thanks
James

30-24. The 60-24 will be WAY too much current, you'd be wasting more than half it's capacity. Or, just get a buckpuck and a 1A wall wart.

 

[slevesque]

Ouch! 48 LED's. I was hoping for 24 using a specific optic. I might go with 2x single 48" T5 HO instead

 

[der_wille_zur_macht]

Your dimensions are really tough. You might be able to get by with much fewer than I'm suggesting if you can get creative. The trick is getting even coverage and good color mixing when the numbers get low. In a "traditional" chubby rectangle tank, that's not really a problem because you can bunch them appropriately. In a super long, super narrow tank, it's just gonna be weird.

Carlco make some elliptical optics that might be worth playing with for an application like this. How high above the tank would you be able to mount the LEDs? Their ellipticals are something like 10 x 40 degrees. If you oriented them along the tank, and mounted at an appropriate height for the 10 degree axis to meet the width of the tank (unsure how high that would be!) you'd probably be able to use far fewer total LEDs - maybe in the ~25 - 30 count range.

If I were you, I'd order three or four each of cool white XP-Gs and royal blue XP-E/XR-E, a few of the elliptical optics, and play with mounting heights with the LEDs spaced 4+ inches apart from each other, and see what it looks like.

 

[slevesque]

I don't know how high I'll put the fixture. It all depends on the light source I choose. I agree, too few LED's will have a "spotlight effect".

I've checked the Carlco optics. Nice, the oval shape

I just want to keep the cost low. It's suppose to be a fun nano project and not a full SPS reef money pit .

 

[der_wille_zur_macht]

Consider the tradeoff between upfront cost (higher for LEDs) and longterm cost (lower for LEDs). If your tank will be up for more than a year or two, the LEDs will probably end up cheaper thanks to lower electrical costs and no lamp replacement.

 

[HeneryH]

x - deleted sorry

 

[zangmann]

So what is the consensus on swapping out T5s for LEDs?

Let me explain:
I have 4 48"T5s used for actinic supplement to 2x250w MH.

If I wanted to swap to 3W CREE leds (RB) would it be a wattage for wattage swap?

54/3 = 18 led per T5? Or would 18 leds be enough to replace 2 T5 bulbs?

 

[der_wille_zur_macht]

It's probably closer to needing 50% the wattage of LEDs to equal T5, based on reports from people who have switched - but there's a LOT of leeway. Especially in "supplemental" lighting.

Which T5 lamps are you using? How big is the tank? etc.?

 

[The Grim Reefer]

Id think 12 would be enough to take the place of a blue plus if your just looking for color rather than PAR

 

[der_wille_zur_macht]

FWIW the royal blue LEDs put out similar PAR per watt as the cool whites, so they're good in that respect, too - not just for color. I've seen more than one case where someone tried to add a handful of royal blues to an existing light rig "for supplementation" and they end up bleaching their corals to death because they used too many.

 

[zangmann]

Good info thanks for the quick replies.

Tank is a standard 55 gallon. Current T5s are UVL SA, 2x ATI B+, KZ FP.
2x 250w MH @20kK

I'm most interested in sunrise/sunset periods, but if I can get some extra growth/pop out of the LEDs, why not?

 

[The Grim Reefer]

Good info thanks for the quick replies.

Tank is a standard 55 gallon. Current T5s are UVL SA, 2x ATI B+, KZ FP.
2x 250w MH @20kK

I'm most interested in sunrise/sunset periods, but if I can get some extra growth/pop out of the LEDs, why not?

You should get good PAR from them. Based on PAR readings I've seen here I would say the RB's are producing as much or more PAR than the cool whites. The whites had higher readings but the PAR meters don't read light in the deep blue spectrum very well so an extremely blue source like a Royal Blue is going to have more PAR that a meter will read.

 

[stugray]

Hey Grim,

Have you tried your PAR meter with different LEDs to see what they show?

I have some interested parties in: Blue, Red, Deep Red, Cool White, & warm white.

I am just curious what a PAR meter sees with the different colors. I know that not ALL wavelengths "count" in the PAR measurements.

Stu

 

[The Grim Reefer]

Hey Grim,

Have you tried your PAR meter with different LEDs to see what they show?

I have some interested parties in: Blue, Red, Deep Red, Cool White, & warm white.

I am just curious what a PAR meter sees with the different colors. I know that not ALL wavelengths "count" in the PAR measurements.

Stu

No I havent. What happens is the PAR meter doesn't see blue below a certain range and over estimates red up to about 620nm so reading a wide variety of spectrums and trying to compare which is best is hard.

The red box represents the range of PAR starting at 400 at the left and 700 at the right. The Blue line is the sensor response, green light is plant response. You can see on the right side the Blue line goes over a cliff but it is beyond the range of red most lighting sources have. On the other side you get the drop off starting right about 500nm and goes over a cliff (but not like the red) at around 450nm which is right in the sweet spot for most blue light sources.

 

[wld1783]

crazy glue, just a dab will do you...

Loctite Super Glue Gel, thick, great for corals too

Dont Use Crazy Glue The Cyanoacrylate May Fog The LED Lense!!!

From a warning in the CREE PDF.

I used the non-toxic Loctite Stick'n Seal

The Cyanoacrylate fumes are also used by cops to get finger prints.

Bill

 

[wld1783]

That's more like the answer I was looking for. Leave it to Stu to shoot me straight. So the locktight 5min epoxy is fine? I was leary of using super glue because of the VOC sticking to any residue on the led. Epoxy it is then.

+1

Also the 70 and 80 degree optics for the CREE XR-E just snap on and dont need glue.

Bill

 

[wld1783]

Hi guys, what would you recommend for a 96"x8"x8" ? Low-medium light corals only: GSP, ricordia, zoas.

My 48 XRE LED fixture on a 24" x 8.46" heatsink covers 30"x 24" with the Cree 70 degree optics. 30" depth 12" above the water. More Lux than a 400watt MH

For a 8" wide tank you should be good with 12 LEDs for every 24".

Then again this might be too much or too little depending on optics.

Bill

 

[HndMafia]

THose of you using the meanwell 60-48D's:

Do these drivers put off heat? I am considering stacking them on top of each other but don't want to create heat issues within the drivers.

--a side note, I test fired my 48 xre lit section tonight and I think my fish are gonna need sunglasses

 

[akindbro4u]

THose of you using the meanwell 60-48D's:

Do these drivers put off heat? I am considering stacking them on top of each other but don't want to create heat issues within the drivers.

--a side note, I test fired my 48 xre lit section tonight and I think my fish are gonna need sunglasses

Mine get HOT. Don't know if that's normal, but that's my experience.

 

[skippyreef]

I am going to try to find a cheap ballast casing for my drivers and fan cool it.

So far I have the 24" x 8" heat sink with the 48 LEDS wired up and it rocks. The other identical heat sink has 84 LED's on it. I think I will be hanging that on the ceiling literally with 60 degree optics and dimmers.

I am going to work on the 36" sections this week. I finally received my LEDgin 400nm 5 watt UV leds and I am thinking on mounting one dead middle on each of these without optics. I want to keep chalices in this area so I will be using more blue than white light and I think I may increase spacing between the LEDs and use wider optics.