4ft led fixture

[axe_man16]

I need a bit of input on where I should place my LEDs. I have 2x 20"x4.5" heatsinks, 9 white led's, 7 royal blue, 2 blue, 2 red and 2 green.

My tank is quite narrow at 48"L x 13"D x 20"t

This is how laid the LEDs out.
http://i1223.photobucket.com/albums/dd511/AXE_MAN16/IMG_7068.jpg

Incase you can't read the writing in the picture here is the layout.

w---rb---w ---b-----------------w---rb---w---rb
----r ----g ----- rb----------w------ r----g
rb--w-----rb---w----------------b---w---rb---w
I am planning on having the fixture 6-8" above the water.

What do you think about the placement?

[Enigma]

To reduce the disco effect you might like to make four clusters of LEDs: two clusters on each heat sink. Basically, squish your groups of five together. Which will leave you with an extra RB.

Don't glue anything in place yet. I had a huge amount of help from some forum members in placing mine, and what I wound up with was completely different from what I started with.

Edit: in case you haven't seen it . . . Here's what happened to my LEDs when forum members chimed in: http://www.canreef.com/vbulletin/showthread.php?t=89518

[axe_man16]

http://i1223.photobucket.com/albums/dd511/AXE_MAN16/LIGHT.jpg

So would this be better. Not the best picture, but I squished the clusters in a bit.

The whites have 45 lenses and the blues will have 60. red and green will not have lenses.

[axe_man16]

Bump

[Enigma]

That isn't quite what I was thinking. I'll see if i can find some time to draft up what I'm thinking would be best at work today. I should have time to do it.

[axe_man16]

Thanks for your help!

[sphelps]

Are these going to be dimmable and on different drivers?

Personally I for one have a hard time working with the layout, odd number of white and RBs, only two blues, and too many whites. Also I don't think you have enough LED's for a 4ft fixture, especially with optics. Are you open to suggestions regarding changing a few things other than placement?

[axe_man16]

These are the numbers that was suggested by Modular LED.

Remember that my tank is only 13" wide. I would like to use the amount suggested as I have spent enough money on this fixture as is.

Yes I have 3 dimmable drivers.

[Enigma]

I'm thinking more along the lines of this layout:

http://i1035.photobucket.com/albums/a435/Iasgair/axe_man16-Default-000.jpg

Sorry. I just got rush pipeline edits and I haven't had the opportunity to think about the colours, yet.

[axe_man16]

That could be done. I would have to extend some of the connectors but that is fine.

Thanks again

[Enigma]

If you don't want to order any different LEDs, I think I might try this:

http://i1035.photobucket.com/albums/a435/Iasgair/axe_man16-Default-001.jpg

I swapped the positions of the centre W and RB.

EDIT: Just keep in mind that I don't know a whole lot about this. I'm just learning, too.

[sphelps]

I'd think long and hard about this as I'm guessing you're epoxying these boards down making changing them later rather difficult. Shelly did probably as good as it gets but it's still going to be awfully color spotty. I can't imagine why anyone would recommend this quantity and ratio of LEDs, you'll end up running whites at like 30%, blue at 100%, and reds and greens at 5%. Especially with 45 degree optics on the white for a 20" tall tank, is the plan to hang the fixture really high?

For a little more you could have gone with 3 drivers powering with 8 boards of blue, 8 R-blue and 8 Neutral white and I wouldn't use optics at all. I don't think reds and greens would be much benefit if you use neutral whites but if you really wanted them after trying this combination you could easily add them with a lower powered string to prevent spots.

[Enigma]

Here's the link to my .DXF (in case anyone wants to fiddle with it some more . . . I just got really badly slammed with work).

https://www.dropbox.com/s/c6iykgsuzlvfc45/axe_man16.dxf

It can be downloaded by clicking the "Download" icon in the top right of the screen after clicking the link.

[axe_man16]

Thanks. The layout is similar to one of the layouts I did up a week or so ago. I guess if the colors are a bit spotty I can try taking a few lenses off to help.