LEDs for replacing PC actinic?

[Masoch]

Hi,

I have a silly question that's probably been asked before / chatted about in one of the LED threads ... but, after reading through a few of these threads, I'm going cross-eyed from the wiring diagrams. Be easy on me, I'm an arts grad ;)

Here goes: right now, I have 2x64 PC's over my puny 20 gallon tank. I like the light with 1 10k and one actinic, but ... LEDs are calling. Could I replace my PC actinic with LEDs? I know there are LEDs of appropriate wavelengths (420-440 nm) ... so, could I wire up a dozen or so 5 watt 420 nm LEDs ... and toss the actinic bulb? Would the critters in the tank be ok with this? Would a mix of wavelengths be better? Would the intensity be comparable, more, or less than my current actinic bulb? Since LEDs are more focused than PCs, I would guess there would be more light hitting the tank, but I'm not sure.

As I see it, I'd have less heat, lower power consumption, and nice shimmer ... for relatively cheap.

Thanks in advance, folks!

[moonpod]

The problem is $$$$$. LED's of appopriate wavelength I believe are fairly expensive currently--you need a lot of them. I think given time though....Yes less heat, long bulb life, but NOT cheap.

[moonpod]

The problem is $$$$$. LED's of appopriate wavelength I believe are fairly expensive currently--you need a lot of them. I think given time though....Yes less heat, long bulb life, but NOT cheap.

[DJ88©]

Masoch,

take a peek at this thread. Over a 20 gallon if you were to use four, at the most, six of these LED's you could probably do it. You can buy them in 470 and 455 nm wavelengths. I am thinking about doing this over a 33 gallon tank and a 29 as well.

You can buy them at Active electronics. A bit pricier than run of the mill LED's($18 each) but they are rated at 1W each.

http://www.canreef.com/phpBB2/viewtopic.php?t=3849&highlight=

[moonpod]

ach, didn't pay attention--20gallon tank, yeah, you might be able to do LED for a reasonable price.

[StirCrazy]

this is a 25 gall tank i am playing with LED actinics on. This is only using 3 LEDs at a cost of 2.00 each. for complete coverage i would recomend 8 or 12 LEDs

http://members.shaw.ca/s.l.s/diy/led/3_370nm_led_top.jpg

http://members.shaw.ca/s.l.s/diy/led/3_370nm_tank_proper1.jpg

http://members.shaw.ca/s.l.s/diy/led/3_370nm_tank_proper.jpg


Steve

[Masoch]

Thanks for the info!

I was half-expecting responses like, "My god, you'll kill your livestock!" But to see at least someone else working off the same idea is good enough encouragement for me.

The Luxeon LEDs seem to be perfect ... except for the price. Bright, low power, good diffusion, decent wavelength, very long life (100k hours?!?!). But there are cheaper ones around ...

StirCrazy:

I love the look of those lights. Do you have a part number?

[StirCrazy]

ya, right now I an thinking of using them in conjunction with a timed dimmer circut to act as moonlight and the lead in for the actinics.

I also feel if you have enuf of them you could use them as actinic lights, but this would be for looks mainly. I have gotten them to change the color of the tank with two 55watt 10000K PC, but not much, but then again I was only using 3.. 12 of them would be enuf to make it a Ice blue/white I think.

anyways here is the 470nm ones
470's (http://www.eled.com/product.asp?catalog_name=LEDs&category_name=&product_id=E7113PBC-H)

and here are the 430's I just got
430's (http://www.eled.com/product.asp?catalog_name=LEDs&category_name=&product_id=E53MBC)

Steve

[freakyreef]

As long as were looking at LED's, I came across a site that banks them and has a regular 120 AC screw base. A bit pricey, but interesting nonetheless.
http://www.ledtronics.com/
Lots of LED stuff.

[120GREEF]

Check these out they might work.
http://www.xoxide.com/lazerled.html

[stainlessdonkey]

How do you wire these up? I would love to set some up as moonlights!

[hlehmann]

Originally posted by StirCrazy
ya, right now I an thinking of using them in conjunction with a timed dimmer circut to act as moonlight and the lead in for the actinics.

Putting LEDs on a timer is fine, but they're not really dimmable, being DC devices.
I use 4 blue LEDs for a moonlight effect, running them from a 12 volt wall-wart power supply through appropriate resistors. I just leave them on 24 hours a day, since they consume minimal power and are completely overpowered by the PC lamps anyway. Since the LEDs that I'm using have a quite narrow beam, I scuffed them up with some course sandpaper to light up the tank more evenly.

[StirCrazy]

Originally posted by hlehmann
Putting LEDs on a timer is fine, but they're not really dimmable, being DC devices.

They actualy dim rather nicely, How does DC relate to being not diamable.. I know lots od DC devives that can be dimmed or have speed controled just by lowering the voltage given to them..

Steve

[stainlessdonkey]

Yes, but does anyone here know how to wire up LED's or a like to a schematic?

[northstar]

StirCrazy - where did you find the LEDs for $2? What model/brand are they?

[bwilkinson]

This place has super bright blue LEDs for $0.75 each and white LEDs for $1.10 each. I bought a bunch of each and plan to collect some empirical evidence on the practicality of using LEDs as an alternative light source. Unfortunately, I haven't had time to assemble the system due to I am extremely busy at work.

http://www.elexp.com/opt_hr10.htm

[StirCrazy]

Originally posted by northstar
StirCrazy - where did you find the LEDs for $2? What model/brand are they?

I ordered them from

http://www.eled.com

Steve

[northstar]

Stircrazy - nevermind I see your links above - Thanks

[drake51]

Not sure how much all of the parts will cost for a diy moonlight, but champion lights has a blueline moonlight (http://www.championlighting.com/e/env/0001GYFNU8QNJg0e9k5y6r9/Products/Lighting/lighting.html?link=/Products/Lighting/moon.html) for ~$50.

[mbelding]

Some of you have requested wiring/schematic help for using LEDs. Email me at markbelding@hotmail.com for advise, and include information about your application. Sorry, but I don't visit ReefCentral often enough to be responsive here.

Also, someone questioned LED dimming. There are two ways to dim LEDs. First is to reduce current through them. A standard LED can run up to 25mA, but is visible to a human all the way down to 5mA. The disadvantage of doing it this way is most methods of reducing the current "spend" the current instead in a resistor, so you're not saving any power this way.

The other way to dim an LED is to flicker it. LEDs can turn on and off so fast that your eye perceives it only as dim instead of flickering. This is the most power efficient way to do it, and is how that digital alarm clock on your nightstand does it. Can fish perceive the flickering? Would it stress them out? All to-be-determined.

Mark Belding
Santa Barbara, CA