Help me with my Evil cluster LEDs

[Yodeling]

Ok so I've been doing a lot of research in preparations for my own LED build. I have most of the gear bought, and my Typhon controller is built (I will modify the code to run 5 channels). I'm just not confident enough to pull the trigger on the LEDs yet.

This build will be for my 120g 4x2x2 tank. I'm looking to add as much halide-like shimmer as possible, so "evil" cluster seems to be a good route. Here's what I'm thinking.

Ch1
2x Vero13 4000k 90 CRI

Ch2
2x Luxeon K-16 Royal Blue

Ch3
12 Luxeon ES Cool blue (4 tristars)

Ch4
4 Luxeon ES Cyan / 2 Luxeon ES Lime (2 tristars)

Ch5
6 Hyper Violets (2 tristars)

Is this going to be a good mix? Will this provide enough PAR? This will be for an SPS tank mainly. I like Radium-like blue look and really like the shimmer of Halides (only thing I miss). I plan on using 50 degree reflectors on the Veros and K16s. What are my options for optics on the tristars?

 

[jedimasterben]

I would take a look at my build here: http://reefcentral.com/forums/showthread.php?t=2415740

It's a hybrid unit, but PAR and color without the T5 can be anything you want it to be, even without lenses for the best color mixing. I would probably clone that array, but the reds are optional (I added them since I needed something to fill that spot on the 3up stars) and swap the M for the K8 or K16 (the K16 would be really, really, really powerful and I would NOT recommend lenses on anything).

This was my previous array before moving to a Vero-based one: http://www.nano-reef.com/topic/323517-ct-7567-the-ledt5-nanobox-hybrid-evil-cluster/?p=4497149

and here are the PAR readings from it: http://www.nano-reef.com/topic/323517-ct-7567-the-ledt5-nanobox-hybrid-evil-cluster/?p=4510707

That array only has two LED clusters, and with the T5 turned off, it was very noticeable where the light from the LEDs really stopped, I did not have full coverage of the tank and it didn't look great IMHO. Color was great, though

 

[Yodeling]

Ben, great info! I was hoping you, specifically, would chime in. Indeed, I'm looking to replicate your setup as much as possible. My thoughts on using two clusters was that I would get more of the typical MH shimmer. Would it help if I raised it up higher? How is the shimmer with 4 clusters?

 

[jedimasterben]

If you used optics, then yes, the shimmer is intense, but it is not quite like MH shimmer. Each LED will be making its own shimmer, and depending on the hang height (which would need to be very high to prevent killing what you put under it) the beams would intermingle a little, but you'll still have minimal banding. This is more something you'd need to test out for yourself and see if you like.

Mine are around 26" above my sandbed, and PAR is still nuts with the Vero running an effective 500mA, M at 1A, for approximately 5K lumens (1,230lm each) of white and 54W (~6,750mW each) of royal blue. PAR on center was almost 150 from those two alone.

For your proposed arrays, you'd be using approximately 6K lumens (2,910lm each) of white and 93.5W (23,375mW each) of royal blue. Adding optics on top of that, even 50 degree, will increase PAR exponentially, which is one reason why they weren't even considered on this latest array lol.

PAR is pretty linear with output as long as the base LED and distance remain the same. The Luxeon M and K both use the Luxeon T diode, the only difference is that the K uses multiple ones on a PCB and the M uses four in one package. So if my 8x M that produce 54W of light were suddenly producing 93.5W, PAR would almost double at the same distance - bringing my 87 reading up to 150. Adjusting for more distance, since your tank is already 24" tall, say to 36", the reading becomes right around 78 PAR. Adding 50 degree optics will focus the light, and in that reduced area, and PAR will increase from around 78 at least to 187 if my math isn't too rusty. PAR will drop off very quickly from that center point, so you'll have a very intense hot spot.


I would probably recommend you to go with four LED clusters using Vero 10 and K8 as the base, and then build from there, or

Also, what kind of Radium is it you like? Run on a proper ballast or on underdriven and really blue?

 

[Yodeling]

In the past, I ran the the Radium on the PFO M135s (pulse start). I also liked the XM20k on same setup. Both were very blue and I liked the look (as did my corals). I never cared much for fluorescents (T5s, VHOs etc) due to its very uniform look and no shimmer, although IMHO they were capable of producing far superior color and coverage.

To avoid the extra cost, I think I will try the two clusters and add more if I don't like the gaps. If I remember correctly, my MH on spider reflectors allowed for some shadow in the middle as well.

Since I can dim these, I'm not really worried about too much color/PAR (though I obviously don't want to waste money), but I really want to make sure I'm not missing anything for the spectrum and the overall color I'm after. I added more cool blue as compared to your build to make up for the lack of T5s, but maybe that misses the mark. I took out the red, which you said wasn't necessary. Should I add more lime or green? What does that do for the color? Should I add other violets or are the hyper-vs fine?

 

[zachts]

You could do a pair of "Extra Evil" Clusters. More than one smaller cluster more closely together, like 2 by (4 mini clusters in a 12" footprint), no optics and slightly diffused splash gaurd...... or built into an old MH pendant with reflector cut and cannibalized......

Everyone likes overkill right!

Besides you can get two vero 10 for same price as 13 and basically the same on the luxeon K, though I do think you need a few more of the lime/cyan with all that blue to get good blending. More Violet wouldn't hurt either, I'd add some in the 410 to 420nm range in addition to the 430nm 3 ups.

 

[jedimasterben]

T5 really don't have all that much more blue - they have europium and mercury, which gets you ~565nm and ~620nm spikes that are, at best, difficult to match with LEDs. Like and standard red cover these two bits of the spectra and do it well.

I prefer a 1:1 lumen ratio of high CRI white to lime and then dimming them at the same percentage, though recently I've been playing with a higher lime percentage, closer to 3:2 in favor of lime. Allows the light to be brighter while also reducing intensity (it's a strange thing that we now have need of a reduction in intensity, isn't it lol).

For the violets, a mix of their hyper and true violet is probably best - their hyper violets have no equals as of this point, both in intensity and spectral coverage from the single diode, but they don't put but a small amount of intensity into the lower near-UV range.

 

[Yodeling]

Thanks for your help! You've given me a lot of answers and (un)fortunately a lot more things to ponder as well. I'll be back with my build thread when I'm ready. Thanks again!