Revisiting LEDs (5mm 20mA)

[skeeley]

I've been searching various reef forums for a while now, and it seems like all of the experiments with regular LEDs has stopped, and everybody is moving to 3W or 5W LEDs.

Has anyone continued experiments with normal LEDs? Standard 3.4V 5mm LEDs can now put out 18000mcd or more. Has anyone had any success with arrays of "normal" LEDs?

I'm mostly interested in good Coraline growth and maybe some low light soft corals. Has anyone had success with arrays of LEDs and good Coraline growth / soft coral growth? Are there any ongoing experiments with this type of lighting? A low wattage lighting system is my goal to save on electric bills. Any thoughts, results would be appreciated.

Thanks

 

[Anonymous]

With the smaller led's it becomes a cost/light output problem. You have to get a LOT of little ones to match a 5W'er. And it's not just the cost of the diodes, it's the cost of manufacturing. have you ever soldered 200 LED's? unless you can dip/flow them it takes hours.
and if you're dipping them you'll need to burn a circuit board before hand. which is added cost.

Also, I dont' think the little ones penetrate the water that well. One bright point of light vs lots of little ones, and the one brighter light will get deeper in the tank.

B

 

[Anonymous]

have you ever soldered 200 LED's? unless you can dip/flow them it takes hours.

Yes I have, and I will attest your back & neck will not appreciate you for bending over doing each little solder.

 

[skeeley]

Thanks for the replies. I don't mind soldering 200 LEDs. I've already created a test grid of 16 blue and white LEDs on a small perfboard, and the output, while very focused, is very bright. If I regulate voltage to 15V, I can create chains of 4 LEDs with an 82 Ohm resistor on each "chain". That means that each chain only draws 20mA. If I put 200 LEDs together, I can light a small tank with approximately 15W and 1A of power. This shouldn't hit the electric bill too hard. I plan to start small and try to keep some live rock alive. If this works out, maybe try a low light coral. If it doesn't work out, hey, at least it will be entertaining .