I bought a few Lumiled LED's for an emergency vehicle light system that I am designing.  They run about $5.00 - $6.00 a piece.  They are blinding when you look at them.  A person could use several of them for a reef, but as John said, it would be spendy.

Alex

Thanks Jake. 

Those would work, they'd be spendy, but they would work (no wonder those flashlights are so expensive).

jfinch wrote: As for LEDs.  I agree with Jake (I think Jake still has this impression) that LEDs are bright enough. Maybe I'm missing something but I don't see it.  Those really bright LEDs are in the neighborhood of 12000 mcd (blue) to 24000 mcd (red) at a viewing half angle of 10 degrees.  If you use an average candela rating of 15000 mcd (you'll want more blue then red) it works out to about 1.4 lumen per bulb.  Let's say you could fit 11,400 LEDs over a typical 90 gallon tank.  That's only about 17,000 lumen.  One 250 watt MH bulb is more then that.  But I must be wrong, 'cause everyone say's they're the light of the future (I've got a skunk clownfish swimming under blue actinics )

Jon,

I think you are missing something.

Check out http://www.lumileds.com.

They have LEDs with 120 lumens per LED, although most are not quite that bright most of them average 30-40 lumens per LED.

I don't think the technology is quite evolved enough yet, but I think it will be soon.

jfinch wrote: As for LEDs.  I agree with Jake (I think Jake still has this impression) that LEDs are bright enough. Maybe I'm missing something but I don't see it.  Those really bright LEDs are in the neighborhood of 12000 mcd (blue) to 24000 mcd (red) at a viewing half angle of 10 degrees.  If you use an average candela rating of 15000 mcd (you'll want more blue then red) it works out to about 1.4 lumen per bulb.  Let's say you could fit 11,400 LEDs over a typical 90 gallon tank.  That's only about 17,000 lumen.  One 250 watt MH bulb is more then that.  But I must be wrong, 'cause everyone say's they're the light of the future (I've got a skunk clownfish swimming under blue actinics )

I don't think they're bright enough yet, but they are super efficient.  Give it time and they'll keep improving.  I think they will be come the lights of the future, or at least the technology behind them will, just not as soon as everyone thinks.

I know what you mean Jon.  I hear the arguements, and I'm not sure what to think.  Although, I do know that my halide wastes a ton of light.  I know this because ever since I got my halides my living room is a whole lot brighter.  Even above the tank.....

Adam

As for LEDs.  I agree with Jake (I think Jake still has this impression) that LEDs are bright enough.

Maybe I'm missing something but I don't see it.  Those really bright LEDs are in the neighborhood of 12000 mcd (blue) to 24000 mcd (red) at a viewing half angle of 10 degrees.  If you use an average candela rating of 15000 mcd (you'll want more blue then red) it works out to about 1.4 lumen per bulb.  Let's say you could fit 11,400 LEDs over a typical 90 gallon tank.  That's only about 17,000 lumen.  One 250 watt MH bulb is more then that.  But I must be wrong, 'cause everyone say's they're the light of the future

(I've got a skunk clownfish swimming under blue actinics )

I love, absolutely love symantics.  I may not have learned much in school, but that is one area I studied.

As for LEDs.  I agree with Jake (I think Jake still has this impression) that LEDs are bright enough.  Those super bright leds, imagine like a panel of 5,000 of them above your tank.  But they are costly, and they don't have that halide shimmer.  
But manufacturing a big panel of them and getting a wide spectrum would be a pain. 

Adam

(oh yah, I don't think combining your spectrum would be fun at all, I just like buying my lights and setting them up on my tank) 

I think most actinic light out there is Red...

Symantics!

Agree on the LED issue.  Although imo, the real issue with LEDs is intensity.  If they could be manufactured with enough intensity it would be fun to mix and match to get the combined spectrum you desire!