LED's for Aquarium Moon/Lunar Lighting

I could have sworn there was a thread on here in the past about aquarium lunar lights but I couldn't find it via search. Does anyone have these or done a DIY project? Some of the off-the-shelf solutions are pretty expensive and bulky (think they include power supply and LED in same case). I saw a setup on EBay that was just the lights (and I guess a driver circuit) which could be run by 12V DC. Any idea if a wall-wart transfomer rated at 12V DC would be "DC-enough" for LED's? I know these often have significant ripple.

Hoping to hear some options,
Matt

The problem with most of those LED moon kits you find online is that they use 5mm LED's and cast a very unatural spotlight effect on the tank. Have a look at my custom made plywood aquarium hood which incorporates two Luxeon I blue LED's. It was a very simple mod and the result is very pleasing to the eye and very natural looking too due to the evenly balanced flood of light in the tank. The behaviour of the fish at night is noticeably different, and for the better in my opinion. It certainly reduces the sudden shock of night and day when the lights come on and off. Anyhow back to the topic of LED's, have a look at the pics below to see how it was done.

The LED moonlight on, close to full brightness at night:


The LED's on low:


The LED's on high:


The LED's off, as you can see i simply used a piece of sheet metal to sink the heat a bit. Heatsinking is not a major issue in this application due to the very low current being fed to the LED's.


The wiring consists of a toggle switch and a variable resistor to control brightness, power is being drawn directly from a wal wart plug.


Outside view of the controls:


The closeup of the luxeon I blue LED, nail polish used to seal electrical contacts from moisture due to evaporation from the tank.


That's pretty much it, construction of this moonlight was fairly simple. If you've got any questions or need some pointers just let me know. I would love to see pics if u decide to tackle a project like this of your own. One thing i forgot to mention is that i leave the moonlight on 24/7 and i've been running it since the begining of last summer.

Very cool... thanks for the great info. I do have a couple questions.

Where did you get the blue Lux's? Are they a certain color/wavelength?

What value pot/variable resistor did you use to get appropriate drive currents?

Is your wall wart 12V or 6V or ...?

I recently ordered a 12 gallon Eclipse Acrylic tank/hood/filter/light system for the bedroom and definitely want to do lunar lights in it.

You probably know this, but you can get timer/power strip combos that toggle outlets for both day and night use (some outlets on during day and off at night and other outlets just the opposite): perfect for lunar lights.

Thanks a bunch,
Matt

To answer your question the Walwart i'm using is from a motorolla cell phone and it's rated at 4v DC and 350ma output, the LED's are wired in parallel. I'm not to sure what the value of the variable resistor was, but i'll look this up later and report back to you. The LED's that i used are blue Luxeon 1's, there are different types of blue that you can use, but i just stuck with the regular blue and i purchased them from Future Electronics. I already use a timer for the main lights in the tank, however i prefer to keep the moonlights on all the time because it slightly improves the colour of the tank. I'm using two 30W powerglo flourecent tubes and the blue led's help bring out more of the blue spectrum and it looks much nicer in my opinion.

By the way my tank is 40 gallons and meausres 3 feet long and two Luxeons gives excellent coverage, you may want to stick with just one Luxeon as two would likely be overkill.

Great info... yeah, with 4VDC I wouldn't think you'd need much resistance. Great use of an old transformer as well.

Time to order some LED's (a few for my other tanks as well) and start this project. I'll make sure to repost when I'm done.

I'm just getting into fishkeeping, having only had a tank for 3 weeks. As of yet I only have 5 glowlight tetras, 2 mollys and an albino frog (and lots of live plants). The tank is about 3ft x 1 ft and about 2 ft deep with light blue gravel.

I built a prototype moonlight using 2 blue and one green superbright LED's with the ends filed flat to create dispersal and loose the beam effect, powered by a wallmat with series resistor. This does look pretty good with a soothing cyan colour, but is not bright enough to make out the tetras unless you get up close to the tank. I am thinking of going for a 'mark 2' version with maybe 5 blue, 2 geen and one red LED (I want to use only 5mm LED's, and am only adding the red to give a little whiteness to the light and help bring out the colour of the tetras, I do not want to use white LED's as they tend to be lacking in the red spectrum).

I am also considering adding a few UV LED's, but was wondering if anyone has any experience of them, and if they would help bring out colours as I imagine they would.

I know that moonlighting is not important for tropical freshwater tanks (only marine setups), but I want a light that will give the tank a gentle relaxing llight that will not be too bright in a darkened room.

Any suggestions will be apreciated, and maybe between us we can create the perfect moon/mood light.