My DIY LED Fixture

[aagresti]

i decided to build my own light fixture. my tank is a deep blue 57g rimless. I was told by Mike at RapidLED that a 250w MH is the equivalent of roughly 24 LEDS. I currently have a dual 175W MH light fixture. I've decided to go with 18 Cree XP-G Cool White and 18 XP-E Royal Blue. All LEDs will have optics (55 deg). There will be 3 Meanwells ELN60-48D, each will power 12 LEDs (12 white, 12 royal blue, 6/6 royalblue/white. this is the layout I plan to use. The 3 additional blue leds are for moonlighting which will be powered by a separate supply (probably a 5v supply with an appropriate size resistor to set the luight output level.) all leds will be mounted on heatsinks. haven't decided if i'll drill and tap holes or use a thermal epoxy. comments? enough leds? different color palette? different layout? etc.
thanks
Aldo

 

[Triple R]

well if you are going to use 36 leds i would say get 3 heatsinks which hold 12 leds each and make 3 different fixtures. spread them evenly apart and you should have enough light. im not an led pro but im about to do a diy led setup. just my 2 cents.

 

[SSV3NOM]

I think you're better off with XR-E LEDs.

I don't see the point in paying more for just for 20% more PAR.

Plus it will allow you to use the LPC driver.. which is a good amount cheaper.

Bill @ Reef Led Lights.com

Tests the PAR at 24" depth.

The greater than/less than flow chart looks something like this

Degrees
70 > 60 > 80 > No Optics.

I don't know about the 55 degree... but seems to be kinda limiting. And for now I think you're limited with the XP-G series.

Hopefully they'll come out with wider optics.

On my 46g Bowfront.. I used the XR-E and initially did a 1:1 (White & Blue) with also 36 LEDs.

1 Blue dedicated, 1 white dedicated and 1 W/B dedicated driver.

Its plenty bright. However I wanted more of a 20,000K look... so instead of getting involved with adding dimmable drivers (because I used constant current - seemed easier and less involved at the time) about 3 weeks ago I purchased 12 more XR-E royal blues.

My lay out consists of

3 Central Rows of Alternating White/Blue

and when I added the new Royal Blue LEDs, I created two front and back strips, consisting of 6 LEDs each.

Actually looks really good. Most guys that have those monster MH setups like JARRETT SHARK, kind of have that type of placement. VHO Actinics on the front and back, and the 3 MH bulbs in the middle.

I also am a "whore" (lol) for the whole radioactive blue LED look, so I wanted more independant blue LED control.

So my initial set up as mentioned was 18 White and 18 Blue.

Now its 30 Blue and 18 White.. and I am much more pleased with the color of the light.

Any new coral I add will just start out on the sand bed and slowly make its way up so it can get used to the light.

*Oh and I used the thermal expoxy with the gimmicky aluminum shavings.

Works great. If you do it "right" - slightly sanding the heatsink surface (where the LED will be placed) and wipe it down thoroughly with an alcohol wipe... you're never going to be able to take that LED off again haha.

If you do it wrong . you can easily pop them off with a screw driver or flat like tool.

As far as actual heat dissipation differences between simply screwing the LEDs on and using the epoxy... I really don't know if there is a difference. All I can say is that the LEDs don't get hot when using this method with a heat sink.

However...

I recently "gutted" my 6g Nanocube's Lid PC fixture and just epoxyed some LEDs right on the reflector, and managed to fit the meanwell driver flush. Actually works great with the original lid's light switch. However I noticed that since the 6 LEDs are on thin piece of what I'm assuming is aluminum or steel reflector they actually get quite hot. Not as hot as the PC bulb that was in there, but MUCH hotter than they feel on the retrofit LED fixture I built for my 46g Bowfront.

Anyway.. theres my errrr.... rant? I guess. lol

Good luck with your fixture Aldo. I'll see you in S.I. next Sunday.

If you have any questions just PM me.

Oh and great choice with going with LEDs! You won't regret it.

 

[aagresti]

ss3v, thanks for the long write-up. I cant do 3 three separate strings of twelve. my deepblue has a huge oveflow in the middle of the back wall (look at my diagram), so i had to play with the layout. as far as the optics, the xpe 55 deg optics is the equivalent of a 70deg on the xre (per Mike at Raipled). I also have 3 60mm stealth fans blowing air on the heatsinks. i'll try this out to start. i can always add 12 blues to change the tint if necessary, see you at Richie's next week.

 

[SSV3NOM]

Ah wow. Sorry I didn't take the overflow in consideration.

The diagram looks great.

In all honesty.. I think the hardest part about the DIY LEDs is really finding the best placement for it. Some people have drilled tanks (like me), central overflows, corner over flows... so the actual layout could be a bit different.

Yeah.. try to leave your self some room if you can to add more LEDs if you want.

As far as the overall color goes.. you might like it.. you might not lol.

All I can say is that the more blue thats in there... the more the colors pop out. Even with all the "daylight" LEDs on.