edited to include only relevant points.
I'm interested in the leds Jake Adams installed on 1200 reef over in Reef Builders. What are you thoughts on the Reefbrite leds ?
http://reefbuilders.com/2010/01/04/reefbrite-actinic-led-striplights-lig...
(Gomer(Tony)): I haven't looked too extensively into those LEDs. With a little speculation, there are somethings I like and dont like about them
like how they are modular. They let you "adjust" the color just like we do with T5's.
One thing I particularly like is that they offer a UV solution. Almost every LED setup lacks 400-440nm. This wavelength is what causes a
fair bit of "pop" that you get with MH/VHOs.
What I don't like (speculation) is that they aren't the "next gen" LEDs. This means that they are likely not nearly as efficient as Cree and their ilk which are now very common in DIY builds.
If you aren't running SPS, I doubt you'll have trouble with intensity. With SPS, I'd be suspicious. I'd personally let others try them a
bit before investing into the setup /end
when tony said 'adjust' does he mean color or dimming thereby changing the spectrum?
(Gomer(Tony)): Eric, by adjust the spectrum, I mean to the same extent that we adjust colors with T5s. Want more pop, add actinic. Want more Par, add more "white".
I could be wrong, but I don't think these have individual dimming capacity (/end
I've heard that even though the new improved LEDs put off more power than a MH, the light gets weaker through
water and is very low at the bottom. I heard that MH is better for lighting if the tank is deep. I like the no heat from the LEDs but they seem they would make the tank all blue-looking. This is a big deal for me since I'm deciding whether to get a NC 150w MH-HQI or the new NC 150w LEDs...
(Gomer(Tony)): matthew, couple things there, and I'll address the easy part first
heat: LEDs do generate a lot of heat. They just don't do it "towards" the tank. Rather they do it through the heatsink. I bring this up
because if you may be thinking of building this into your hood. If you can't pull the heat out of the hood, you can still get substantial tank heating (albeit less than MH of equivelant power)
The other part is often referred to as "punch" or "penetration". LEDs can pack a ton of punch if you have them setup for that. There
is a lot of math behind it (I won't get into it), but it has to do with optics
If you run LEDs without optics, a MH will have more penetrating power (ie, intensity drops off slower). If you use appropriate optics,
LEDs can drop off slower
I have a 130watt LED setup which bleached corals at the top and bottom of my tank which was running a 250watt radium before hand
Can one mount LED lights inside a lumenarc (or other MH) reflector?
(Gomer(Tony)): You could, but I wouldn't. It wouldnt be nearly as effective as idividual optics. Optics work are designed around the location of light. Luminarcs for example are designed to have a MH bulb at the center and so far down. LEDs will be spread out all through the reflector. That's the easy explanation
I can talk to you in depth later if you want to go over the whole optics math behind it
How deep will LEDs penetrate?
That depends on optics. Without optics, you are safe with AIO tanks. You'll probably want to use optics beyond that. I'm using 60deg optics and can probably go an easy 20+ inches. Going 40deg even deeper and so on. The trade off, is that you lose coverage
You can theoretically use something like 6deg optics and pierce down through a crazy deep tank...but you'd need a huge array to get the
coverage
The optics are not the tiny domes on the LEDs. The optics are the ~ 1" clear plastic things
question for tony: what are his thoughts on UV leds. are they necessary or is there already enough 'reds' in the white leds?
(Gomer(Tony)): well, reds and UV are on the opposite end of the spectrum
but I know what you mean
I have had really good growth with just the standard blue/white mix. I don't think there is any red or UV lacking for growth. lacking
UV is more of an aesthetics thing. You lack some of the pop. LEDs do some colors extremely well, but not so well on others.
reds are one of those colors. Some reds scream. Others are a little lacking. Greens all scream. Blues do pretty well too. What you will
lack are whatever fluoresces at 400-430 or so nm
So does that mean MH is ever so slightly more powerful?
(Gomer(Tony)): Matthew, sometimes yes, sometimes no. In general, watt per watt, I think LED systems can put out as much PAR as most MH setups (not talking about those few PAR monsters in the MH arena). I have no PAR measurements. I can say though that my growth under ~130watts of LED is better/faster (ignoring bleaching
than my 250 radium setup
Can the spectral output of individual bulbs be programmed to shift throughout the day?
(Gomer(Tony)): The output of a single LED emitter doesn't change much. You can't really program it. You can get a small color shift when you under and over drive them, but not enough to matter. When people "program" their color or do anything color related, it is all in ratioing one color LED (like white) to another (like blue).
Thoughts on the new LEDs from Acriche?
(Gomer(Tony)): I'm mixed. They are designed around home lighting. They tend to be "warm" adn there is now offered "blue" component (although they technically can do it easily). I'm not 100% sure how they operate, so I'm not sure if you can dim their intensity simply with a variac or similar. No blue and no dimming and then the SW market is killed.
So which would be better for nems? MH or LEDs? Does a 150w LED put off as much power as a 250w MH?
(Gomer(Tony)): Matthew, a proper LED setup and a proper MH setup will both supply enough light for nems
150watts of LEDs is a lot of light (and pretty $$$)
What type of thermal couplings would you need to attach an LED to a heatsink? Is it like a CPU in that it's really smooth just a tad of thermal paste for any minor imperfection?
(Gomer(Tony)): Exactly mike. Thermal conductivity of air sucks. Thermal conductivity of thermal paste is less sucky than air but way sucker than the metal :-D Very smooth and flat surfaces and minimal thermal compound is idea. This isn't a huge deal when lightly driven, but when you crank up the current to say 700-1000mA, you really need to have good thermal transfer (I resurfaced my heatsink before mounting)
The fixture here: http://www.ecoxotic.com/community/wp-content/uploads/2009/10/CoralPlanningMap.pdf doesn't list Acropora sp. Why? Typographic omission or problem with growing acroporas under LED?
(Gomer(Tony)): I'm not sure why it is left off. It could be an accidental ommission or it could be that they don't trust their light to support those high intensity species
What are your thoughts on the recently released Ecoxotics leds ?
(Gomer(Tony)): I'm not familiar at all with them. They are running at low power compared to what I'm familiar with. This may be intentional or a design limitation. There are a lot of "knock off" LEDs coming into the market now. Some may be good, but I don't trust them until proven
I'm not comfortable putting expensive lights over a way more expensive coral tank, and without trusting the LEDs.
Are there certain spec's I should be looking for in leds ? Should I be concerned about led companies going out of business like PFO b/c of Orbitec's broad patent on leds ?
(Gomer(Tony)): The problem with PFO imo wasn't orbitec. I looked into one unit and their thermal management was really bad. I wasn't surprised that LED banks were failing. Heat and current are two things which make or break LEDs. As for LEDs emitters, there are a few good companies I'd support
Cree, Luxeon, Soul are the ones I can think of right now (there are a couple others). Any new LED should be able to draw about 3 watts per emitter. If they are drawing 1 watt or there about, I'd be suspect of it's
efficiency and "age" of technology.
Orbitec is another can of worms. They are the devil.
Do you have an example wire diagram for the DIY impaired?
(Gomer(Tony)): the wiring diagram is HIGHLY dependent on the driver
usually it is 6 LEDs in series and the leds of the driver to the ends.
Have you seen or are there companies working on a type of connector that will allow users to easily replace bulbs with out the need to solder?
(Gomer(Tony)): There are a couple version of the "connector"
PFO had banks of LEDs. 5 LEDs were on one board and if one died you changed the board.
Most LEDs are available on MCPCB. In theory, they can each have their own wiring harness. I don't see this as being economical
What does tony think about the maxspect g2
(Gomer(Tony)): I dont know enough about it to hold an opinion
Are there LEDs that could be mounted inside tanks (like at the bottom edge) pointing up and in?
(Gomer(Tony)): I'm not aware of any that could be, but it is technically possible
just keep in mind that internal LEDs now dump ALL their heat into the tank
Ive seen some LED fixtures in the US market already are they breaking patent laws from Orbitech?
Gomer(Tony)): I don't doubt they are. Orbitech had an original patent claim that they are now trying to expand on. Not every light system falls under their umbrella.
Do you know of a source where you could get fixture housing to place the LEDs in?
(Gomer(Tony)): Cree has a fixture and they just released a new one http://www.creelighting.com/ info on their new on at cree.com
Do you see LED being the future of lighting? or will plasmas and HIDs take the spotlight?
(Gomer(Tony)): For lighting in general, I see them all holding a place.
LEDs work better then the other two in some situations and visa versa. I guess the same can be said in reefing. They all have tradeoffs. I do see LEDs taking a bigger market share than they have now by a fair bit
By bleaching do you mean that the LEDs are so powerful that they bleach corals in the top of the tank? Does MH do this? Would LEDs bleach anemones or bother clowns?
(Gomer(Tony)): LEDs and MH both have the potential to put out excessive light in certain situations which with cause bleaching
Anything on the horizon comparable with the Cree XP-G? Or will it plateau and we should start looking at fixtures?
Gomer(Tony)): The XPG is pretty efficient, but we are only about 1/2 the theoretical efficiency limit
I think it is somewhere around 250 or so lumens/watt theoretical limit for a ~5-6000K Black body LED. (not 100% certain)
I think LEDs are now viable in reefs with th eXPG, but there will be something new coming out every year. I don't think you'll get too much in the next few years without an revolutionary change (right now, everything is evolutionary)
