Your input on my idea to make a led system

[Corvette Reefer]

okay i got a 20 gallon high tank and this is my idea to build a led system. the black would be the heat sink then the color would be the leds and what color they will be and the gray is what i will mount the heat sink to. i would use Cree XR-E bulbs for all them but the reds, the red would be Cree XR-C, id use a BuckPuck 700mA dimming, and a 12V power supply. what do u think of my plan, any recommendations or changes i should do? Also i was woundering what would i mount the heat sinks to for the fixture its self to put on the tank and how do u mount the sink to what ever u want for the cover of the fixture? thanks for the help!

[evilc66]

I would avoid the red LEDs in all honesty. They are very bright (your eyes are very sensitive to it), and will be very distracting. If you want to add a little more red to bring out certain colors in the tank, then use neutral white LEDs opposed to cool white. They aren't as bright, but they help with certain colors.

As for the rest of the layout, I'd add a few more LEDs to just make the output a little more even across the tank. Make 3 groups of 4 LEDs, if you want to keep the layout you have now. Each group would consist of 2 white and 2 blue LEDs. Starting with an even ratio will get you in a 14K temperature range. If you use dimmable drivers, you will be able to adjust from that point, higher or lower. If you are going to use Buckpucks, get two total (one for blue and one for white), and run it off a 24v power supply. MPJA has a good, inexpensive unit from Potrans (24v, 6.5A, $15). Smaller heatsink will work, but will be dependant on a fan for temperature control. If you want to improve things thermally, but still keep it cheap, use a sheet of aluminum to mount everything to. Sandwich the sheet between the LEDs and the heatsink. It will create a much larger area to mount the LEDs to (most small PC heatsinks don't have a huge mounting area), and add more mass and surface area for cooling.

[Corvette Reefer]

okay thanks! so like this?


what is a good website to find all this stuff for cheap? i found this one and it looks good ledsupply.com anywhere u can find these LEDs for about $5 a piece... also when u get a buckpuck dimmable driver do u have to get a special controll to dim them or is it built into it?

[Corvette Reefer]

Also would there be a difference between using Cree XR-E Star and Cree XR-E Emitter? I origanly was gona get the start but the emitter is about $2 cheaper.

Also how do u think this would work on my size tank? http://www.fosterandsmithaquatics.co...3&pcatid=21973

[evilc66]

Stars make life a lot easier for mounting and soldering. Unless you know what you are doing, avoid bare emmiters.

For a good price on LEDs, we (Nanocustoms, we are a sponsor here) sell LEDs and accessories. We don't sell the Luxdrive Buckpuck though, and don't have a simple option for a dimmable driver for 6 LEDs. If you wanted to forgo the color temperature adjustment option, the Meanwell ELN-60-48D will work, and you just put all 12 LEDs on a single driver.

[Corvette Reefer]

i definably want a dimmable driver, but do i need a separate controller or something along with the dimmable driver? or is it built into the buckpuck?

[evilc66]

The version you want is the 3023-D-E-1000. That's 1000mA, externally dimmable. If it doesn't come with a pot (depends where you buy it from), you will need a 5K ohm linear taper pot (easy to find at Radioshack). Buckpucks can be used with a reef controller, but with a little modification. You can't hook them directly up to one.

[fawkes]

Evil has indicated that the red LED's are distracting. Does anyone know about research that tested color needs of corals? Leaves on plants use red and blue and reflect green (that is why we see them as green)..

[evilc66]

Photosynthetic corals use the same chlorophyll A and B as plants, but have more of an emphasis on blue light, around 450-460nm. White LEDs produce a good amount of blue, but just enough red to satify that end of the chlorophyll's needs. The royal blues at 455nm sits really close to the blue response peak for both chlorophyll A and B. That's the basics for growth potential, but certain color rendering issues are still being sorted out.

[fawkes]

Thanks, Evil. It is useful to know. I assumed that there was red in the white LED's. I would think that somewhere someone is trying red/blue to see if they can maximize growth. But if you have to add white to see the stuff, it does make a compelling case for not using just red/blue.

I grow (too many) orchids. Just this week, I ordered a couple of panels of red/blue LED's to try on a smaller growing area. Many of the folks using LED's for plants are not using white - or less of it. It will be interesting to see if there is any change in growth and flowering. If this works I will trade out the 800W MH/HPS combination lamp in the larger growing area. It will probably cut my lighting expenses by more than half. But it will probably mean that I will have to use the ceiling lamps when I am working on the plants...