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_Adrian_
10-14-2015, 07:37 PM
Hey guys...
I seen this thread somewhere but searched high and low and found nothing :)

Maybe someone can chime in on this matter.
In the meantime :)
Im working on my LED fixture slowly and building up the materials needed to start the build.

The tank is a 53 x 24 x 30 ( L x W x H ) Full Reef ( mainly softies ).

I have my main "channels" split up as follows:
1. Cool White 6000K
2. Warm white 3500K
3. Blue 460-465nm
4. Royal Blue 445 - 455nm
5. Green 510-530nm
6. Red 610-630nm
7. Deep Red 660nm
8. Violet / UV 395 - 400nm

LED's are 3W Epistar's with 120 degree optics and using 8x 11.8" x 5.5" x 0.8" heat sinks with active thermal management. Each LED string will be colour independent and have 10 LED's. The Aluminum PCBs will be custom to allow the mixing of colours to avoid the disco effect in the tank. The Cool White and Warm White LED's are 90 degree units.

Before I can move further and design the Aluminum PCB I need to figure out the distribution and scatter :)

Ron99
10-14-2015, 09:54 PM
I've been experimenting with LEDs for many years and if I were building a fixture now I would simply use warm white, royal blue, violet and green. There's really no need for the regular blue in addition to royal blue and red LEDs add little either. But green is useful as it can stimulate some of the red pigments in corals etc.

I have a fixture I built many years ago. At the time I just used cool white and royal blue with 90 degree optics. When i put it back to use over my 120 gallon tank I added in some violet, red and green emitters without any optics just to add colour. It's working really well but I've found i basically have the reds almost turned off. I don't find them useful at all.

Seth81
10-16-2015, 04:35 PM
I agree, no need for all of the channels of light you have mentioned. From my personal experience I would only do:

Cool White
Royal Blue
UV
True violet

If you wanted to keep it simple then just the Cool white and Royal blue.

I've been experimenting with LEDs for many years and if I were building a fixture now I would simply use warm white, royal blue, violet and green. There's really no need for the regular blue in addition to royal blue and red LEDs add little either. But green is useful as it can stimulate some of the red pigments in corals etc.

I have a fixture I built many years ago. At the time I just used cool white and royal blue with 90 degree optics. When i put it back to use over my 120 gallon tank I added in some violet, red and green emitters without any optics just to add colour. It's working really well but I've found i basically have the reds almost turned off. I don't find them useful at all.

Ron99
10-16-2015, 07:56 PM
I agree, no need for all of the channels of light you have mentioned. From my personal experience I would only do:

Cool White
Royal Blue
UV
True violet

If you wanted to keep it simple then just the Cool white and Royal blue.

I would definitely add some green. Have you ever shined a plain green LED on corals? It makes the red colours pop.

Seth81
10-16-2015, 08:15 PM
Sorry I meant Cyan. Yes I had Cyan and it did bring out more reds.

I would definitely add some green. Have you ever shined a plain green LED on corals? It makes the red colours pop.

_Adrian_
10-16-2015, 09:38 PM
Thanks guys :)

I'm planning to control each colour as one single channel. This way not only I can simulate actual weather shifts but also to have peak coral growth.
I will be using 6 panels above a 30" deep tank. with that being said most of the RED and GREEN will be invisible considering the amount of LED's on each panel...

10x CW
10x WW
10x B
10x RB
5x R
5x G
5x U/V

I have 16 HIGH Current Channels ( 8 more if I count the shared dimmer ones and stil capable to deliver 5A or more a channel ) at my disposal. Current setup will be running of 2 x 36V 400W power supplies which are the bottle neck right now, but can always add more if needed. My main concern isnt about the colours, but avoiding the disco ball effect

Ron99
10-16-2015, 10:12 PM
Your PAR for coral growth will come from your blue and white so you'll want some optics on them. 80 or 90 degree with good overlap to get your colour blending as well as even lighting.

I would use the other coloured ones without any secondary optics as they will be just for visual impact rather than coral growth. That way you won't have any disco ball effect from separate colours being focussed in too narrow a way.

_Adrian_
10-17-2015, 07:02 PM
Thanks !!
I was planing to use 90 degree optics on the white's and blue's and the rest were going to get 120 degree optics.

I guess the overall wording is wrong lol
What I'm trying to find out how to spread the LED's on the board to achieve the most efficient blend of colours.

I seen a few different ways of doing this and its confusing

Ron99
10-17-2015, 09:01 PM
it's more complicated with optics and the fact you want to mix cool white and warm white and royal blue and blue which will lead to slightly different colours in different spots. When I built mine I did 4 rows of alternating cool white and royal blue. Each LED in the row is about 2 inches apart. The rows are spaced about 3 inches between them width wise. They are also the opposite arrangement if that makes sense. So if row 1 is WBWBWBWB then row two is BWBWBWBW and row three is WBWBWBWB with row 4 being WBWBWBWB. My 4 violets are spaced out evenly down the centre and the 4 greens and 4 reds are staggered front to back and length wise as well. I don't use any secondary optics on the violet, green or red so I get a pretty even spread from them.

kamloops_reefer
10-17-2015, 11:10 PM
you might want to post over on nano-reef.com there is some great input there from the sellers involved at LEDgroupbuy

_Adrian_
10-18-2015, 01:24 AM
Thanks guys :)

The optics are fairly cheap in comparison to everything else.
The heat sinks for the LED's were $120, aluminum light enclosure ( 52 x 12 x 4 ) was $175, main board of the controller was $60 and the daughter boards were $80.
I'm not even going to mention the hours of R&D I sank into it and the $50 or so of SMD parts, but... in the end it will be a cool package giving the end user 24 channel LED Driver.
Yes... I will be selling the units once I have it dialed in and running right.

Ron99
10-19-2015, 03:49 AM
So you're doing this for yourself or as a commercial venture?

_Adrian_
10-19-2015, 06:29 AM
So you're doing this for yourself or as a commercial venture?

A bit of both...
The Driver will be the venture meanwhile the fixture will be the test. There's also an aquarium controller with full array of accessories on the horizon as well...