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Cold Cathode Moonlighting

2787 Views 6 Replies 5 Participants Last post by  lorenceo
Hi All!

I'm going to add a DIY moonlight to my tank. At the moment I think I will go with Cold Cathode. (Less wiring hassle!) I'm looking at buying a 12" bulb. My tank is 30" accross. My question is will just one bulb be ok? Will the light diffuse out through the tank? I figure if its in the centre that should get most of the tank...


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Don't know about the cold cathode, but I did mine with 4 led's that originally had 18 on a string and were powered by a 4 AA battery pack. They were sold as a christmas light set at target and came in blue, red and white (each set was one color) I bought the blue. I re-wired the led's how I wanted them with spacing and so on and only left 4 on total. I bought a 6V 300ma AC adapter and wired it in...Presto! Works great! I would imagine that one would be enough if you go with the cold cathode, depending on how bright you want it to be. I'm sure someone else has more experience with them.
Thats a great idea, I've not seen anything quite like that here, I would've snapped them up! I've been looking at CC's because they don't require soldering and not so much wiring.

I'm looking for some kind of pre-wired LED's, fingers crossed!! Maybe some of those flexi snake ones...
Looking for pre-wired LED's - Auto Parts store was my source - two nicely mounted White LED's at R&S (they come in blue, but I think white looks a little more natural, if natural at all).

Wired them to a radio shack 3-12v selectable (brightness control) powerblock.
Picked up a power socket so when I remove the cap I can quick disconnect the lines...

They look like this:
What do they look like when on?
Breadhead said:
What do they look like when on?
That turned out to be seemingly impossible to photograph with my camera.
My Canon powershot S10 just doesn't seem to be up to the task, and believe me, I tried every mode I could think of, it just isn't bright enough for the little lens on that camera. I tried manual spot metered, macro'd, "slow shutter", different zooms and camera position, you name the setting on that camera, I tried it.

Even tried a few with some ambient lighting behind the tank and it just washes out the led's.

If someone knows how to get it to do a longer exposure, I'd love to know how. Without a better camera, a picture is out of the question in my opinion.

They aren't that dim to my eye, but even pushing the input to the LED's to 12v, I can't get them to show up.
Helene, I'm from nz too.

Also planning nightlights for a comming up tank (350 litres) and ive seen cold cathodes running. they are very bright.. one 12" will be fine for your tank, possibly too much so i suggest you get an adjustable power supply from ****smiths, incase it is too bright.

Also, a good source for cathodes is here: (sorry if you arent in nz, the site is nz only:p)
dse's website: search adjustable power supply or something..

hope this is of some help..
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