Reef Discussion

Buddy

Member
Mar 13, 2012
3,142
1,526
Ok after all that sucking up I don't feel so bad asking more questions!
Most of this has pretty much been stolen from this thread so thanks for that :D
I have just been making notes in notepad so ill just copy and paste it straight here...

1810mm wide tank
minus 125mm from each end to first led
=1560 from first to last led
= 26 leds, (2 x 13 leds) @ 60mm centres
4 lengths of 26 leds = 104 leds on aluminium U channel

up to 26 exotic @300ma
6 cyan, 6 turquoise
12 violet
---------------------------------
78 white and blue @750ma
13 cool white
26 neutral white
13 blue
26 royal blue

Questions and concerns...
Obviously I am trying to keep the colours to groups of 13 for colour control and keeping the number of drivers as low as I can on the blue and whites.
Would this combination be a bit too white?
Does the number of exotics seem alright? I can play with the cyan and turquoise to add a couple of reds if its worth trying out.
Would dimming the cyan, turquoise and red and the same channel work?
Roughly how far in from the front and the back of the tank would be good to start the leds?
Anything you would change?
 

Rob

Member
Apr 26, 2012
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424
I also see they have another triple. Ocean white Which is another mix. Maybe good for the longer arrangements where these will group the LEDs for you
 

chimaera

enjoy the little things
May 13, 2012
5,473
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Sandringham
Ocean White is an awesome 3-up, those colours need to be close together to blend so makes perfect sense. The cree 3-ups are a good option too, depending on the amount of tank you are looking to cover.
 

Rob

Member
Apr 26, 2012
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424
Assume you would probably only need three types Ocean White, XT-E 3up and a few violets. I've nearly talked myself into this DIY stuff again + @macca_75 build has inspired me
 

chimaera

enjoy the little things
May 13, 2012
5,473
2,295
Sandringham
@Rob yes, you could easily build just using those three items and have a top notch full spectrum build. You know you want to, rather than a Mitras ;)
 

MagicJ

Moderator
Jul 11, 2011
9,650
3,761
Hobart, Tasmania
Assume you would probably only need three types Ocean White, XT-E 3up and a few violets. I've nearly talked myself into this DIY stuff again + @macca_75 build has inspired me
Yes, that's about it :)

For me, the choice between the 3-ups and individual leds would just come down to price.
 

Rob

Member
Apr 26, 2012
743
424
Has there been much discussion on clustering LEDs or simply spreading them out along the tank length. I see a lot of the 3-up implementations now seem to prefer clusters of 8-10 stars. Now having a 6x54W powermodule with even light distribution I cannot get this concept of having groups of light sources. (never had MH which I suppose is the same concept of centralized light sources)
 

chimaera

enjoy the little things
May 13, 2012
5,473
2,295
Sandringham
We had a fair bit of back and forth on Macca's build thread. All I read suggests that clustering is generally the best approach to ensure colour blending and with the right optics you won't 'see' any difference in the resulting light on your tank. But even distribution can work too, particularly for larger tanks.
 

slin1977

Member
Jul 13, 2011
3,476
1,661
Sydney
I would definitely consider them...

My only concern would be the concentrated heat created by 3 led's in close proximity - you would want to ensure you had good cooling capability.
Yes that is the concern - that's why the max drive current for these LED clusters are 700mA. Those clusters should be fine for a build.
Less current, less heat and add more LED to make up for the loss in light output. If you ran your build at around 500 mA you prob would not need additional cooling.
Interestingly a 39watt T5 fixture produces about 70PAR at 100mm without a reflector and 275PAR with a reflector.
With this in mind the hard thing to try to overcome in ones mind is that you really don't need to chase high wattage numbers with LED.
IMO LED behave very differently to other more traditional light sources. Especially Cree LED it seems that the quality light that a Cree produces does not require quantity to back it up. Since turning down the lights in my tank I have had better results with my LEDs and coral colours. Finding that sweet spot takes a lot of experimentation.
 

macca_75

Member
Apr 22, 2012
2,125
844
Hey @Rob, I need to put a small order in for the remainder of the LED's from Rapidled.

Do you want to throw a few OCW 3 ups in, we can wire them up and have a look for real instead of all the theory?
 

Rob

Member
Apr 26, 2012
743
424
I was thinking the same however have not seen OCW or 3-ups on their site. ledgroupbuy also have no stock. Would of liked to of done a dummy build using one of your four 6" heatsinks just to do a quick compare between the (3-up/OCW/Violet) cluster and your current selection.
 

chrispc66

Member
Apr 24, 2012
317
160
Nice thread. I run an old DIY system. Used to be all Crees, but over time these have fizzled out. All replaced with Bridgelux LEDS now. I'm very happy with them. Currently run 4 banks of 13 LEDS over a 4' tank.

Colour is a mix of B/RB / 6.5K-10K W / 450 nM pinks / Greens. I have experimented with reds, but these were overpowering so replaced with pink which gives a nice hue. I also invested in UV LEDS, gave them a run for 4 months, bloody things done a lot of damage, so now gone.....all are driven between 9 to 12V / 750 mA. The Bridgelux LEDS so far are coping at this level fine. I also run 80 degree optics.

I also run a vertex blue LED setup used for additional asthetics which I run in the morning / evening.

My reef is mixed, and my SPS / LPS are going well. I do struggle with purple SPS, but pinks go fine. My shortcake and milli go well and growth throughout is great.

My PAR throughout was a little down, 300 at the water line down to 75 at the substrate, but the optics really improved this where now I have 450 at water level, 300 at most SPS to 125 at the substrate.

Thanks for posting a nice thread, very interesting.