Picture of Fish tank LED moonlight / moonlighting
This instructable will show you how to safely add LED lighting to a fishtank/vivarium.

I've tried previous versions of night / moon lighting in the tank, but none were up to the task:

Moonlight v1 - waterproofed high power LED's attached to the side of the tank - these gave pretty good lighting but there were too many pools of light in the tank, and also the number of wires was pretty unsightly.

Moonlight v2 - Cold cathode lighting (from a PC mod kit) , however as Ive got a large tank (180ltr) and I needed to extend the wires from the cathode tubes to the inverter - however when I did this I found that they no longer worked anywhere near as well (it seems this is a known issue with cathode lights).

So....back to Maplin and moonlights v3 is here!

If you want to see the tank please take a look at Fish Cam where there are 2 streaming live cams! To see how I did this you can view my other instructable HERE.
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Step 1: Be safe!

Picture of Be safe!
C:\Users\Will\Desktop\Fish tank moonlights - Copy\IMG_2543.JPG
Before adding any more electrical stuff to your fish tank please, please install a RCD (Residual Current Detector) onto the power supply, these cost about £10/$20 and will save your life!

Water + Electricity dont make happy fun!

If the choice is dead fish or dead people, i know what I'd choose.

Admittedly Ive got a bit more under my fish tank than most (2 Cameras, Firewall, Router, Wireless gateway, 2 Web cams, 2 timers and more.!) but this is a worthwhile investment!
JIMMCCRANK3 years ago
Very nice it looks fantastic at night. This is something I will be doing in the future. Thanks very much.
JustXtreme4 years ago
 what were the stats on your power supply?
billytkid (author)  JustXtreme4 years ago
Sadly I havent measured the usage, but its certainly low, and 100% way way lower than the heater in the tank!
Very nice looking results. I commend you on this. I've been planning on doing something like this in my snake's terrarium, hopefully mine will look somewhat as cool as yours.
hey does anyone know where i can get an LED strip online??? ive been searching for a while and cannot find anything long enough for my 4ft long tank
billytkid (author)  xvitox4 years ago
etd5 years ago
It`s really nice the way you plan it with those phono connection
i was searchin 4 a way 2 do it
for 3 aquariums it`s 2 nice
keep the good job
beff506 years ago
ahhh so you live in England. well i live in Newport Vermont. and i am setting up a 30 gallon tank i think. (that is 25 uk gallons to you) i just use a purple florescent fish tank lamp witch seems to be suitable. soon i will be setting up a salt water tank.
Z7867 years ago
I did exactly the same except i used cold cathode tubes (blue ofcourse). i find they are brighter than LED's, i used them in my cars footwells, and with a 12v transformer, they workd indoors. il post up a picture of my tank soon, 2 tubes makes the tank look stunning. and i think the fish like it. greatt instructablee!!!!
halsir7 years ago
I had a blue cold cathode light from my old computer. Since my aquarium has a dry area for the lamp, I stuffed the light in there with the fluorescent tube. Also, I put a piece of cardboard and tissue paper around bulb to darken it closer to moon light brightness... looks cool. i have a cloudy water problem at the it glows.
carl87gt7 years ago
I love your tank. This is a great instructable. I have a 75 Gal tank and I am using a cold cathode setup for my moonlights. My tank is only 4 feet long so they worked good for my setup. I use two plug-in appliance timers. My moonlights come on 30 minutes before my fluorescents turn off. Then my fluorescents come on in the day 30 minutes before my my moonlights turn off. I run the moon lights for a few hours at night, then total darkness, then moonlight for about an hour in the late morning, then fluorescents for a good chunk of the day.
editkid7 years ago
Works a treat, thanks! I added a little potentiometer right after the adaptor, in order to dim the light to just the right setting. Yes, nice one!
billytkid (author)  editkid7 years ago
Wicked! Have you got any photos?
Yep, this is one with both lights on, the fluorescent daytime light and the LED lights. I used two strips of 15 LEDs.

The dimmer control - which was really easy to add on the main cable going to the lights - is great, as it allows you to look for a really comfortable light level for you and the fishies.

I'll try and get one with just the LEDs on, but it's hard in total darkness to get a good shot. I'll try with some background room light, like you did in your rather nice pics!

Slightly higher res image here.

Nice instructable, clean job. I love this effect. but I'm worried about something; all the leds flashlights and lamps, advice that you shouldn't point them at the eyes. I see my fishs as more delicate creatures. Maybe this can get their stress up and get then prone to get sick. Or I'm just talking nonsense, and it doesn't do anything to them? (mine is:53L fish tank 9 zebrafish 6 guppys and 1 cory)
billytkid (author)  SamuraiGoose7 years ago
Hiya, I see your thoughts but in all honesty I dont think this is an issue. As the LED's are all above the waterline the light gets heavily diffused by the water so the fish cant directly see into the LEDs. Also they are significantly less bright than the overhead strip lights which are on all day!
you dont get as much algee if you dont leave it on all day the light coming in the room is enough
billytkid (author)  andrew1017 years ago
If you live in a house with lots of light..... but if you live in a terraced house built 105 years ago in London and the tank is in the corner then you need the lights, as I do! I get no algee.
jd0061637 years ago
Very Cool...Thanks for the instructable!
Is a vivarium a virtual aquarium? In any case, good idea and awesome fish tank!
thetitan7 years ago
Nice! I made one of those from scratch few months ago for my 20 gallons tank. I didn't have a nice LED strip like yours, i had to solder every LED separately and had to calculate what capacity resistor i would need. I like how you placed yours. I might have to get one of those strips and make a new light. Right now mine are just laying on the glass. @billytkid - UV/black lights are bad for your fish. actually they are bad for anything withing 20 inches. Before i found out that, i had swapped my florescent bulb for a UV one, but i had the same experience. The light simply did not penetrate the water deep enough.
phenoptix7 years ago
The lights look good and I'm sure the fish like the pool o light effect (just played the monkey island series through again so love o' anything!).
Just one mutually beneficial tip, try my websitefor your leds rather than maplins, we're loads cheaper and supply great products.
Nice job, I used just 4 LED's spaced in the light fixture on my 30-Gallon tank, and bent the leads to minimize the "pool O' light" effect on the bottom. It too a while for my Goldfish to get used to the moonlight, but after a year It seems to be jiggy with it. It's a cool effect when the room lights are out.
Mitten7 years ago
Hmm... I might have to use this with UV LEDs for my glofish... Awesome!
billytkid (author)  Mitten7 years ago
Hiya, I tried UV LED's before hoping that they would show up some funky colours, but sadly they just didnt seem to have enough kick to show up anything when any background lights were on in the room. Put up some photos when done, will be cool to have a look
LasVegas7 years ago
Beautiful work and results! Great Instructable!