LED as main light

[cannon2222]

believe me i want the idea of leds as the main light to work, but as far as i can tell its only being tried on tanks that are smaller than a 100. i was just being curious thats all.

[Gomer]

Ok, I know it isn't coral and all, but I though you'd like to see an update of my plant project. I think that the results can be reasonably applied to corals though, especially if you switch a couple white LEDs for blues.

28day update http://www.aquaticplantcentral.com/f...es/28_days.jpg

[cannon2222]

i read that some of you asked about computer power supplies not wanting to work without a motherboard... that version of power supply is for the newer a-t-x computers... if you use a power supply that is from an old a-t computer this should work because it has a manuel power switch. hth

phil

[chucklez]

There is a marked difference between the two of them. Now, is this the same tank?, or two different identically prepared tanks? and what is the water depth?

Before I invest the money on LED as a main light such as mine, I think I will try it on a 55 first.

Keep up the good work guys!

[Gomer]

These are two identically prepared tanks. I am using those little (~4x6x4") critter tanks that you can get at most pet stores....like what you would keep your pet crickets in *L*

The PC tank is lit with a 7watt AZOO palm light. The LED tank is the 7x1watt luxeon stars.

[Gomer]

well, doing a little nano tank, so I also had fun with a new LED light *L*

Converted a Zalman CNPS3100 cpu heatsink to mount the LEDs. (probably enough heatsink to passively cool 3x3watt stars instread of the 1watters on right now). Also threw together a quick and dirty DIY contant current source. makes a really nice little "micro halide"!!!!

[Gomer]

tossed some water in the tank (super nano..DIY tank). An anubias nana for color. A little printer paper for backing.

bask in the shimmering glory!

[minfinger]

Cool idea...How much was all that, well just the lights and the heat sink. And your DIY power source.

[Gomer]

I had 3 extra luxeons so I decided to put them to use. Also made that tiny DIY tank (~4x4.5x6") to experiment with starphire glass (love it!). They are ~ 9-$10ea

The heatsink was an old one that I no longer use.
I've seen them as little as $20 for this model new. I am thinking of slapping on 3x 3wat stars on this later on Enough heatsinking for it

had some scrap aluminum so that I could rig up a mounting onto the heatsink.

The constant current source was just a couple bucks in parts. The AC-DC power supply was just an old one to an old cordless phone.

[Rikko]

WRT to computer power supplies:
The ATX (post-1999, say) power supplies are quite a bit fussier to get going on their own. I had a great URL explaining what needs to be done (I think there's a new channel that needs to be active or somesuch - the link was for converting them for science lab use).

AT (old school) power supplies still require a minimum load to operate (wasted a couple of evenings figuring that out, then read it elsewhere). I'm not sure exactly how much, but I was able to use one when it was hooked into a motherboard just fine. Running a couple of LEDs and two CPU fans didn't keep it on for long, so it's probably somewhere on the order of 100mA or so. Should be plenty if you're running more than a little moonlight.



Also found an interesting link (may have been posted in this thread recently - I haven't stopped by in a while and didn't read every post until now): http://www.advancedaquarist.com/issu...03/feature.htm (Effects of Narrow Bandwidth Light Sources on Coral Host and Zooxanthellae Pigments)

Abstract: Concentrating various coloured LEDs on spots of a rose coral had varying results. Blue LEDs caused a colour change to pink but the authors thought this was a sign of good health despite no growth. Red LEDs caused bleaching (!!). I didn't read it in excruciating detail yet but I don't think they made any conclusions regarding green, yellow, or UV.

[Obi-dad]

That is an interesting article, but one thing to keep in mind is that they were testing with Pocillopora which is commonly pink. So blue LED on a coral does not necessarily mean it will turn pink, just that in Pocillipora it did. It would be nice to see similar tests done with Acro's.

[MalawianDude]

sandisct, how is that White LED's workin out for you? where u able to completely wipe out all other lighting except for ur array? I just finished makin the prototype moonlighting crossed with red Led's am going to have to work on making a huge one with white led's and blue led's/. do you have some better pics of the wiring, i am a lil confused on that. on my i ended up running one strip of wire down for positive and two outside for negatives, each led wired to resistor. powers up great. I'm just lookin for an easier way to wire them together on the big one. kinda interested in the copper strips i'm assuming you would just solder them to that strip then? o yea reading this whole thread in one sitting will take some time so grab a 12 pack and read away..for those new to this thread

[Gomer]

Any updates from anyone on their LED project?

[micaheli]

With an ATX power supply, its super easy to deal with. Just jump(short) the BLACK and GREEN (pin-13/ground and pin-14/pw-on) wires on the atx (20pin ugly connector) connector.

Enjoy.

Micah

[bzzbee2]

Well i will say that the blue lights when i point them directly at corals... they make the corals project amazing colors. my pink zoos look very pink and the little tenticles almost look red, my green zoo turns yellow, and my RBTA glows amazingly.

[Gomer]

[Gomer]

Not a reef, but results none the less

[MadTownMax]

wow gomer, that's very impressive

[minfinger]

Pretty cool test. How did you determine the number of the plants to put in those little tanks?

[Gomer]

Just experience I guess. I am a planted tank junkie

each tank started out with 5 species...2 small cuttings of each. 3 species really took off and 2 didn't. The 2 root feeders had no substrate ferts (virgin substrate) and that most likely accounted for things.

[MalawianDude]

amazing difference, i have an order of LED's comin in and am workin on the wiring plans for it, perhaps one more order and should have sufficient lighting for a planted tank, but here's the question, is when then is c02 necessary? we haven't really been able to determine a measurement for a tank with lighting from LED, like with plants it's like 3-4 watts/gal. then higher needing c02 introduced into the tank. any ideas?

[dcoufal]

FRESHWATER TANK:

I'm currently running 4x40w fluorescents over a 125gal freshwater tank with plants (anacharis & parrot's feather).

[dcoufal]

FRESHWATER TANK:

I'm currently running 4x40w fluorescents over a 125gal freshwater tank with plants (anacharis & parrot's feather).

Any idea how many 10,000mcd LED's I'd need to equal my current 160w of light? 250? 500? 1000?

If the number is reasonable, I'll swap the current DIY lighting for the new LED DIY lighting.... anything to lower heat and keep the elec. cost down!

Dwain

[Gomer]

you are probably looking in the 1000 range (crude guestimate)

...just imaging wiring up that many LEDs...also, how are you going to power that type of array?

[Rikko]

I did a little math on the nanoreef forums a while ago and nobody contested me, so I guess it added up.

Here's what I got:

6400K T5 tube draws 28W and puts out 2750 lumens (this is the data sheet I have handy).

A T5 tube is 5/8" in diameter, and an LED mount needs 5mm. Rounding off, you can stuff 3 LEDs in the space where a T5 sits. Now, we run them lengthwise.
LED is 5mm "long", and we'll go the same 4 feet as the T5 tube. Those 4 feet in metric gives around 1220mm. We can stack, end to end, 243 LEDs.
Now 243 rows of LEDs with 3 LEDs each gives about 730 LEDs. This is now occupying more or less the same amount of space as a single T5 tube.

Now to light output. If we run white LEDs at 10000mcd (they're rated at 8000mcd but you can drive them a little bit harder without too much damage - I accidentally dumped 16V into one the other night. That was very very pretty for a second), that's 10 candela per LED, or 10-12 lumens (I've read conflicting reports). Let's call it 12 lumens.

12 lumens times 730 LEDs = 8760 lumens.
Recall that the T5 tube = 2750 lumens. That's a big difference.

The best part is that the tube is putting out 360 degrees of light - you need reflection to get most of it back. The LEDs are already focused down - no reflectors needed, unless you want to mount them on mirrored acrylic to redirect light bouncing off the water surface (hell, you could submerge them if you wanted, I guess. They're just epoxy capsules on the top).

Of course, each LED putting out 10000mcd is drawing 30mA. That's a total of 22 amps, or 2400W. Ouch.


The efficiency is kind of interesting though..
T5: 2750 lumens / 28 watts = 98.2 lumens/watt
LED: 12 lumens / ~0.1 watts = 120 lumens/watt.
Theoretically LEDs should get you farther, and their directional qualities are nice. Now read the rest of this thread (and others, most notably on nanoreef) to find out why it's not practical or realistic.