DIY fishtank LED lights? Any ideas?

Question

I'm thinking of making a set of LED lights that I can mount to my fishtank to act as spotlights. How safe are LEDs when they get wet? Is there a way to use them underwater? Finally, what's the best way to power them? I'm thinking of using a PC power supply, but suggestions will be welcome.

Answer 1

Holy cow - interesting that you asked this, because we're thinking about re-wiring ours.

My fiance wired his own using all items found at Radio Shack. I'll have to ask him specifics for tomorrow as to exactly what everything's called (he's sleeping now), but I'll give you a rough idea on how to do it tonight.

He started with four LEDs (we chose green, because we thought it would look really cool), and he wired them together in parallel using some kind of red-coated wiring we got at Radio Shack. We'd also picked up a switch (like you'd use on a wall), and he wired it into that. From the switch, it went into a battery holder that held four AA rechargeable batteries. We got tired of charging the batteries, so he then picked up an adjustable AC/DC adapter (again, from Radio Shack), and he wired it in to that - then we were having problems with flickering, so he was able to adjust the voltage as needed (I think we finally settled on 9, but I can't be too sure). He's since re-done the lights using blue, because it looks much better.

If you're dead set on doing it yourself, your best bet would be to buy the LEDs online (Radio Shack sells 'em for way more than you get them online) - try Ebay. The other half got ten blue LEDs for, like, $7.

The only downside to doing everything yourself is that you cannot expose it to water (as there is exposed wiring) unless you can figure out how to encase it so that it's ok. We mounted ours in the actual fluorescent light fixture so that they never got wet.

Honestly, though, it's cheaper to buy the whole moonlight sets online. Drs. Foster and Smith have awesome moonlights that they sell relatively cheap, but you can only choose from red, white, or blue. Here's a link: (and they're on sale right now, too!) http://www.drsfostersmith.com/Product/Prod_Display.cfm?pcatid=12760&N=2004+113544

I believe That Pet Place sells decorative lighting that can be used underwater, but that's a little on the expensive side: (never mind - they've come down since I've last looked) http://www.thatpetplace.com/Products/KW/F46FX/PgNo/1/Class/Aquarium+Ornaments+Laser+Lighted/Shopay00.aspx

Answer 2

Birdistasty gave you good info! I've done the same thing since the pre-made sets are *way* overpriced. The LED's themselves are sealed so you only need to seal the soldered electrical connections on the back of the LED. I used aquarium silicon to totally cover any soldered connections whether they were going underwater or not. It's also not a bad idea to use lead free solder (both for your health and your fish). PC supplies are overkill for this purpose but if you've got a spare laying around it's fine. Just make sure you follow the power recommendations for whatever LED's you choose (i.e. connecting 1.5 volters to 12 volts is a bad idea).

Answer 3

There are LED light sets for sale on eBay. Just google underwater aquarium lights and you will get tons of info and sites to visit. Maybe even try DIY underwater aquarium lights.....

Good luck.

Answer 4

that is very nice DIY and it is not that hard to make, yes do go with the power supply and to make them water proof just build a case for them out of plexi and seal it with silicone for aquarium and let it cure for a full 24 hours. Good luck on your project.

Answer 5

ya