Make your own moon lights for less than $1

corrado007

Active Member
I wanted some moon lights for my 60gal so I decided to try to make a set. It’s a VERY basic project if you are a DIY sort of person. Simply put, it’s just 2 LEDs (light emitting diodes) powered by an old cell phone charger. If you’re a DIY type of person like me you don’t throw any old electronics away. Since almost all of us get new cell phones every year or two when the newest gadgets are added to them we’re left with a box full of old cell phones or at least the extra chargers if you sold the phone on eBay. Assuming you’re this type of person, you also most likely have all of the necessary materials sitting around perhaps with the exception of a few ultra bright LEDs which should cost less than a buck. Since the project was a success I decided to do a write-up and therefore went back and recreated some steps for pictures so please excuse any steps I didn’t take photos of as I didn’t want to do the entire project twice.

Requirements for this project:
1) Basic knowledge on how to solder.
2) Being a pack-rat so you happen to have an old cell phone charger lying around.

Tools/materials needed:
1) Wire cutters/strippers
2) Soldering iron with solder
3) Heat shrink tubing & a lighter (or electrical tape)
4) Rubber grommets
5) Drill and bits
6) 2 ultra bright LEDs (rated at ~ 2.5 - 3 volts)(white, blue, or which ever color you want, I used white)
7) An old AC (wall plug) cell phone charger with an approximate 5 volt DC output.
8) Extra wire, depending on how long you need the cord to be.
9) Ridged wire or coat hanger (just a few inches)

CellPhoneCharger.jpg


You can see that this one has a 4.6 volt output.
ChargerSpecs.jpg



Procedure:
1) Read each step in it’s entirety before doing the step to ensure that you understand it so you don’t break something (light bulbs) or have to undo something.
2) Gather all your materials and tools
3) The first step is the only step where it’s up to you to be a little creative because most aquarium light fixtures are designed slightly differently. Unplug your light fixture and put it on a stable surface. Locate a safe place to drill into your fixture from the outside into the reflector/bulb “chamber” (if your bulbs have a clear plastic shield over them you’ll want to remove it for this). You will most likely want to drill from the back since this hole is where your moon light power cord will be coming out. While ensuring that you don’t drill through any wires/ballasts in the fixture, drill a hole large enough to pass the wire and a coat hanger through. (you should remove your bulb(s) at this point because they’re expensive). Also be sure that the place you’re drilling will allow enough room for the LEDs to not bump into/interfere with the bulbs when they are reinstalled.

Here's where I drilled my hole. You can refer back to this pic for later steps too.
Wireintotheback.jpg


4) Now remove any sharp burs from the metal/plastic casing of your light fixture and insert the grommets in the newly drilled hole, one for each layer of material you had to drill through (this depends on your light fixture, I needed 2)
5) While heating the soldering iron, cut off the plug from the cell phone charger at the end that plugs into the phone so you’re left with the wall charger with a few feet of wire still attached to it.
6) Slide the wire from the AC adapter through the new hole(s) which should now have insulating rubber grommets installed in them. You will be passing the cut end of the wire from the outside to the inside (where the LEDs will be).
7) Split and strip the two wires and slide heat shrink tubing over them before soldering the LEDs.
8) Solder the LEDs to each other attaching the anode of one to the cathode of the other (negative to positive); this is called wiring in series. When done you have two LEDs soldered together with one free anode and one free cathode (negative & positive). Put heat shrink tubing on the leads that you just soldered between the two LEDs and shrink it with the lighter or neatly wrap the exposed joint with electrical tape.

Here are the two LEDs in series.
LEDsinseries.jpg


9) Now solder the two wires from the charger (which you already stripped and slipped heat shrink tubing over them past the bare/stripped portion) to the two remaining leads of the LEDs making sure to attach the positive output of the charger to the anode (positive) side of the LEDs and the negative wire from the charger to the cathode (negative) side of the LEDs.

Here are the LEDs with heat shrink tubing and being soldered to the charger wires.
LEDsandheatshrink.jpg


10) Before shrinking the heat shrink tubing, plug in the adapter to see that the LEDs light up.
11) Assuming they light up, unplug the adapter, slide the heat shrink tubing over the exposed soldered joints, and use the lighter to heat and shrink the tubing in order to insulate the wires.
12) At this point you should have NO bear wires or LED leads showing. They should have all been insulated with either heat shrink tubing or electrical tape.
13) Next, slide a length of coat hanger or stiff wire through the same hole as the wires to add support for them so the LEDs don’t just flop around in the reflector/bulb area. I put some heat shrink tubing over my coat hanger before I slid it through the hole in order to insulate it and give it a nicer appearance.
14) You can tape or zip tie the LEDs to the coat hanger and position them in the middle of the fixture so they point at the reflector.

Here are the LEDs positioned in the fixture and attached to the coat hanger.
LEDsinstalled.jpg


15) You will want to take the end of the coat hanger which is sticking out of the back/outside of the fixture and bend it to a right angle, trimming off excess more than an inch long (here's where you can look back at that earlier pic of the back of the fixture). This can now be used as a handle to swivel the LEDs inside to achieve the desired lighting effect (depending on how they are aimed at the reflector they will illuminate the tank differently). I also put heat shrink on the “handle” to give it a better appearance.
16) Now you can put back together any part of the fixture you took apart and reinstall your bulbs.

Here are the bulbs installed and the LEDs on.
LEDson.jpg


17) You’re done! Just plug your new moon lights in and enjoy. I chose to put mine on a timer opposite my tank light photo period so there’s always some light on.

New moon lights plugged into a timer.
Chargerpluggedin.jpg


Notes: LEDs draw very little power and therefore are no strain at all on the charger. I keep mine plugged in all the time and the moon lights run for 12 hours a day (when ever the main lights are off) and the charger never even gets warm. Seems to be totally safe and just those two little LEDs give a fairly dramatic lunar effect when it’s dark in the room. The picture I have posted doesn’t do them justice since light was coming in through the blinds and I couldn’t choose the perfect setting on my camera to capture the effect.
MoonLight.jpg
 

evallarta1

Member
Great write up! Ive worked with LEDs before and one thing I would recommend is test everything first. Put the whole circuit together (without solder) and make sure it works. Its really easy to get the LEDs confused and put negative to negative, or positive to positive. Or even put it backwards and then have the circuit not work. Then you have to unsolder them (PITA) and start all over.
 

BigAl07

Administrator
RS STAFF
Sounds like a VERY simple project!! I wonder how you could adapt this to some type of water proof tube so to make a submersible light for a FUGE or something!!

Allen
 

InLimbo87

Well-Known Member
Yes very nice project. I was actually pondering what I was going to do for moonlights for my new tank, now I have an easy and cheap solution. Thanks!!!

:)
 

bbl_nk

New Member
You should be able to pick those LEDs from RadioShack or some other type of electronic geek store that has components. They also come in a variety of colors now as well.

Great post and AWESOME idea with the cell phone charger. I think I have about 5-6 in the garage I'm going to dig out and give it a shot. I'm planning on a wood hood enclosure and am thinking about experimenting with different colors across the length of the tank (maybe a red/white/blue look).

Now I have another project to add to the DIY list :)

MUCH karma my friend. When I start my experiement, I'll be sure to post the results!
 

corrado007

Active Member
One quick question though, where did you buy the led's from??

As bbl_nk said, you should be able to get them at Radio Shack in various colors. I actually bought mine on eBay some time back. I got them from an auction like this eBay: NEW 30X 5mm BRIGHTEST WHITE LED LAMP 55,000mcd +30 Resi (item 250122325371 end time Jun-02-07 17:30:00 PDT) where you get 30 or so of them for $15 shipped. I use them for all sorts of projects now and again since I have so many left over from what ever project I bought them for. Like the example auction said, they came with resistors so they can be used with higher voltage but if you simply wire them in series this also allows them to be used with higher voltage and eliminates the need for resistors which heat up quite a bit. By the way, you can of course find them in all colors on eBay as well. Good luck!
 

reefer3

Member
I'm going to give this a try, but I was woundering if I could tap into the wires and run more bulbs off of the charger or is that too much. I'm want to do about 4 bulbs.
 

corrado007

Active Member
I'm going to give this a try, but I was woundering if I could tap into the wires and run more bulbs off of the charger or is that too much. I'm want to do about 4 bulbs.

Typically LEDs need about 2.5 - 3 volts which is why you wire them in series so the load drawn by the two combine is 5 - 6 volts which is the output of the charger. If you were to wire more than 2 onto the circuit I believe they would become dim. You may be able to solder two LEDs in parallel, and another set the same way and finally wire those two sets in series but I'm not sure, I'd have to play around with it. The other option would be to find a higher output AC adapter from some other old gadget that puts out around 12volts. That size adapter isn't uncommon. HTH
 

reefer3

Member
Ok Thanks for the info. I do have a old home phone charger that I think is 12 volt I and I have a old power wheels charger that I think is 12 volt I may give that a try. Thanks again.
 

corrado007

Active Member
Ok Thanks for the info. I do have a old home phone charger that I think is 12 volt I and I have a old power wheels charger that I think is 12 volt I may give that a try. Thanks again.

Hey reefer3, you actually got me wondering about it and I didn't want to instruct you incorrectly so I went out to my garage and tried it out. I used another 4.6v Motorola charger and took four 5 volt (quite common as well) LEDs iwired n parallel and it powered them just fine. You could do 4,6,8, or how ever many LEDs you want (to an extent) if you wire them in parallel . I was using 2.5 volt LEDs in the initial write-up so I put them in series so that the 4.6 volt output of the charger would be a good match for their voltage needs (4.6v charger & 2 2.5 volt LEDs in series for 5 volts). I really all depends on the voltage rating of the LEDs you use and the charger you have. You'll need to play with it a bit. If you want around 4 LEDs you may want to just get four 5volt ones from radio shack and wire them in parallel assuming you're using a 4.6 volt charger as I did. HTH
 

reefer3

Member
I went to my radio shack and they were going out of buisness so I got a good deal on them. I picked up 4 LEDs like you have but they are 3volt for .25 each, then I picked up 4 screw in LED's which are 12 violt for 1.00 each. I installed 3 of the screw in ones in my canopy and and hooked them up to a old power wheels charger and they work great. I have some pics and I'll get take some more at night to see them in action. The only bad thing is they didnt have blue just red and green so I got the red ones. BTW thanks again for the info on this. Heres a pic of the screw in one I got.
Picture172.jpg
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And here is a pic of them installed.
Picture176.jpg
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corrado007

Active Member
Well done reefer3, it looks like you've got a set of moon lights for just a couple bucks. Red should give an interesting effect at night, you'll have to post some pics of your moon lights in action.
 

reefer3

Member
Well they didnt give off enough light to get a pic I could see it but its not bright enough for me so if I can today I'm going to add two more. I think the reason its not giving enough light is because the lights are in a plastic case and I think its blocking most of the light.
 

Whiskey

Just some guy, you know?
If you don't mind me jumping in here,.. I use blue 4W Childrens nightlight bulbs for moonlights,.. one per 2 foot of tank and it works great,.. plus there easy to put out of the way. I pay about $3 for the socket,.. and about $4 for 4 bulbs,.. just wire a cord to the socket and your off to the races, or simply mount a children's nightlight in your canopy, just don't drop it in the drink :D

You can see them in the back of the canopy in this pic:
100_9182.jpg


Whiskey
 
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