Will this layout work or suck?

[ronnie]

I'm planning to retro fit 36 LEDs into my aquactinics TX5 hood on my 40B frag tank. I'm pulling three T5s out and leaving the outer two in place. This will give me a good taste of LED, but leave my security blanket in place until I'm brave enough to pull the plug. :tongue:

Anyways, I've done a stunner strip - DIY style, but haven't done much in the way of full on fixtures. So here is where I'm at: Blue is Royal Blue, Yellow is White (perhaps a mix of cool/warm/neutral?).

Do I need to mix it up a bit? The plan is to use 60º optics for at least some of the LEDs. Fixture will likely be around 12" off the water, but can go much higher/lower if needed, as they are on yoyo pulleys.

The idea is to build an aluminum frame with angle, and then attach some heatsinkusa.com 5.88"x1" to the frame (12 to be exact). Spacing on the heat sinks put the LEDs around 2" or so apart, and spacing is about that (or a shade less) for each of the three LEDs on the heat sinks.

I have plans to run this through my RKL as well, so I'll be dimming it, too. I am tentatively planning to run the RB on a parallel strip with resistors and fuses in place (a total of 24) and then run the whites on a separate driver so I can dim to taste.

Am I way off base? Lead me to water if so. :bigsmile:

 

[Troylee]

I don't see anything wrong with the colors or lay out... I think you got a plan already hehe..

 

[ronnie]

Do you think I'll need some active cooling for these? The fixture has an acrylic shield, but also uses a single fan currently to blow across the bulbs.

I could pull the shield out if needed, but I would prefer to keep it in just to keep it closed up from my 3yr old son

 

[gar732]

I would personally go with a solid heat sink and a couple of fans. I'm sure there are people that will disagree with me but it's cheap insurance on your investment. Better to have it and not need it than to need it and not it, I live by that lol. The problem that I see with the 1" heatsinks is that they can't disapate as well and I think the fans will cool a solid heatsinks better. Especially since they will be inside an enclosed fixture. I'm planning something similar and I will have 4 fans, two at the center blowing down on the heatsinks and the other two at the ends pulling air out of thefixture.

 

[ronnie]

The problem is that one solid heatsink is a lot of extra weight - and from my reading (somewhat limited), it seems most are overkill anyways.

If I can find a big one (or two) cheap, then I'll go that route. Otherwise, I'll stick a couple extra fans in it and call it a day.

I'm a noobie for sure - but it seems the 1" heat sinks would give pretty good surface area, as they are open on all sides, which would mean pretty good heat dissipation?

 

[gar732]

It probably is over kill but thats the way I do everything, lol. I have 24 LEDs on two 6x8 heatsinks and a fan blowing down on each one and it doesnt even get warm. If you want to use the 1" I would run it length wise so that the air from the fans can run along fins of the heatsinks. I would definitely through a couple of fans in there. I think they are like twenty bucks for a pair and power supply from reefled, like I said cheap insurance. As for the optics if you going to use XREs bill did some testing and the 70 degree optics had the best results.

 

[ronnie]

Thanks gar.

 

[Paul B]

I think those all blue LEDs in the center wil give you a noticable blue streak. I know in mine I can definately see where the blue LEDs are and the white.
I used aluminum tubing for a heat sink. The PVC 2X4 in the center houses a couple of cheap computer fans, there are large holes in the tubing where the fans are and air is forged through the tubes. The 36 LED fixturs stays at room temperature.
The system is also on pulleys that easily raises to about 12" over the water.

This is all in a closet so you don't see any of it. The fixture is lifted by the counter weight which is the plastic container filled with lead shot.

 

[ronnie]

Thanks Paul - that looks really good!

Any thoughts on LED placement so I won't see the streak?

 

[Paul B]

I did half white and half blue. You can't put too many whites or blues together or you will get definate color areas. Just alternate white and blue

 

[Troylee]

Mine I went like this...
Bbwbbwbbwbbwbbwbbw
Bwbbwbbwbbwbbwbbwbb
Bbwbbwbbwbbwbbwbbwb
Bwbbwbbwbbwbbwbbwbbw
Etc no problems with blue streaks etc... Here is a picture it's hard to tell but looks perfect..
The lightning strike looking parts are the white the rest is blue...

 

[ronnie]

Thanks Paul and Lee

I'll redo it and see how your layout looks Lee - I will eventually move to five strips if the three work out well - or do you guys think 36 LEDs on a 40B (16" high or so) would do well for SPS in the top portion? This is a frag tank - so no rockwork, just acrylic frag racks.

 

[Troylee]

36 LEDs will grow sps in the sand and still bleach them!!!! I can't stress this enough there very powerfull even my current display there bleaching sticks and stuff with no optics... Work your way into them man... They don't look bright but they pack a mean punch!!!

 

[Paul B]

Mine I went like this...
Bbwbbwbbwbbwbbwbbw
Bwbbwbbwbbwbbwbbwbb
Bbwbbwbbwbbwbbwbbwb
Bwbbwbbwbbwbbwbbwbbw

This looks perfect.

36 LEDs will grow sps in the sand and still bleach them!!!! I can't stress this enough there very powerfull even my current display there bleaching sticks and stuff with no optics... Work your way into them man... They don't look bright but they pack a mean punch!!!

This is true, my montipora's were growing beautifully with the MH lights and with a couple of weeks under LEDs they bleached.

 

[ronnie]

Cool!

I have my layout changed to the above (only three rows, though).

If it works out, I will probably just drop the last two T5s out of the lighting routine. That would then save me some energy and bulb costs - which would be nice.

Would you say all cool whites? Or should I mix in a couple neutral whites or something else?