Lets talk LED's..............

[jezzeaepi]

I left the bulb thing out of it because the question was on electricity, but they certainly are expensive. Some people change their MH every 9 months, others wait 12 months or more. Same with t5(for supplementation). Some people change them every 6 months, but others wait over a year. If you are only using your actinic supplementation for sunrise/sunset, then your t5 will last many years before replacement.

LED technology has come pretty far in the last few years. I imagine that the new systems are cheaper to fix, but I know that with some of the older LED systems atleast, if an LED went out, it was quite costly to repair. The older systems were a little finicky, but I imagine that the newer systems are less prone to breaking. Does anyone have experience with having to do a repair on an out of warranty LED fixture? What kind of things can break, and how much do they cost? This, imo, is something that also must be considered. The risk of broken LED system comes with a much higher price tag then a burnt out ballast.

 

[tat2z_21]

So with the outbreak of LED DIY's and people saying PAR values comparatively I found this article written by Dana Riddle.

Product Review: A Comparison of Two Quantum Meters - Li-Cor v. Apogee — Advanced Aquarist | Aquarist Magazine and Blog

In this article the author goes on to explain the two different commonly used PAR meters.

One thing that we have to understand is that all white LED's regardless of the type , manufacturer, or wattage, has a significant spike in the 430nm to 460nm range. Then on top of that people typically have a 2 to 1 ration of blues to whites. Which the choice of blue is always the Royal Blues which are 430nm.

So neither the Apogee, or the Li-cor are true in that range. The apogee underreports that sectrum more then the Li-Cor, but neither report accurately. So wouldn't it be fair to say that without actually having a perfected way of testing, that we get away from the PAR number comparison's.

 

[Katchupoy]

I just want to tag along.

Build my 36 x XP-G(w), XR-E(b) crees Dec. 2010. Thats on a 75g (4') tank. 14 months later, lights running now at 75% intensity. Cannot move it up further without my RBTA's hiding and not showing up. Will get there (100%) someday Posted my build here at RF, but did not worked out maybe because were not ready yet to switch over to a different technology. So far, so good. Also build a controller to dim it up and down, nothing fancy, you can find it here.


So far it works great. And like everybody said, LEDs has a very specific and narrow spectrum, so looking at it might be dim or not bright enough compared to other lighting system. A lot of people always want to overdo systems, the more the merrier. But this is not true, so be careful not to easily be carried away.

And for the OP, hope im not too late... If you are thinking of building it from CREE's. Here is a simple calculator (for reference only) just to give you a ballpark.

Cree XP-G simple calculator

 

[jezzeaepi]

Thanks for the link tat, I will give it a read.

 

[jezzeaepi]

One thing that we have to understand is that all white LED's regardless of the type , manufacturer, or wattage, has a significant spike in the 430nm to 460nm range. Then on top of that people typically have a 2 to 1 ration of blues to whites. Which the choice of blue is always the Royal Blues which are 430nm.

So neither the Apogee, or the Li-cor are true in that range. The apogee underreports that sectrum more then the Li-Cor, but neither report accurately. So wouldn't it be fair to say that without actually having a perfected way of testing, that we get away from the PAR number comparison's.

Wouldnt this be true though for both LED and MH? I know that my bulb has its largest spectral peak at 450nm. Therefore isnt it a wash?

 

[oceanreefs]

Hello, I just spent the last 2 weeks assembling my Red Sea Max light hood with a mixture of LEDs, everything came out great I purchased my LEDs from a company in California called rapid LED. Michael was a big help visit his website rapid LED. Okay list get back to talking LEDs after assembling everything the color is fantastic the intensity is okay I'm trying to grow SPS corals I'm not really sure if these LEDs can do it, so I went ahead and installed 3 250 W each double ended 14,000 Kelvin medal halides. With the combination of the LEDs in the metal halides we will definitely grow corals. I'll try to get some photographs to show you what I did with my hood ,

so stay tuned. Phil

 

[trido]

I think you misunderstood my post Jesse. I wasn't comparing the radion to a 400w fixture. I was comparing my DIY 180 watt LED to a 400 watt MH.
At 75% it only uses 135W.

I feel confident comparing it to a 400w MH because it is lighting a three foot tank from end to end with SPS at both ends and near the bottom. I order to light this tank with MH from end to end I would have to hang a 400w MH two feet above the tank and IMO a single 250 can't do that.

Also, can you show me the math that works out to

In tridos case, this would amount to a savings of ~$94 a year in electricity.

I was actually being generous with my MH/VHO Vs. LED comparison over my 210.
I ran my VHO's 13 hours a day and only priced it out at 10 hours. Also, in a 13 hours cycle with my LEDs four of those hours are used ramping up/down from 3.6watt up to 108 watts and back down. Only during my high noon blast does my fixture ramp up to the total 135 watts for four hours. My electrical calculations of saving $339.72 a year were very conservative for the sake of easy math.

 

[jezzeaepi]

I think you misunderstood my post Jesse. I wasn't comparing the radion to a 400w fixture. I was comparing my DIY 180 watt LED to a 400 watt MH.
At 75% it only uses 135W.

I feel confident comparing it to a 400w MH because it is lighting a three foot tank from end to end with SPS at both ends and near the bottom. I order to light this tank with MH from end to end I would have to hang a 400w MH two feet above the tank and IMO a single 250 can't do that.

Ahh I see what you are saying. Yah there is no efficient MH solution for tanks whose width or length is an odd number of feet(3', 5', 7', etc). You are either using too many bulbs or too few.

Also, can you show me the math that works out to $94 a year.

My point was that to do a sunrise/sunset effect, you really only need to run the t5 supplementation in the morning for an hour and at night for an hour. During the day, I have a hard time seeing a big difference with my t5's on or off because the MH are so bright in comparison. Therefore, you could turn them off for 7-9 hours during the middle of the day, and save a lot of electricity, and make your bulbs last a lot longer. I think I will start doing this myself actually. $94 = .320kw x 9hr x 365day x $.09


My comparison of the 400w to the 120w led fixture was in terms of depth penetration. If you look at this thread here LED with Optics PAR Measurement - Reef Central Online Community (which is a better version of what I originally posted) At shallow depths, LED puts out thermo-nuclear levels of PAR, but it quickly falls off with depth. At a depth of 15 inches, the par has fallen to about 300. If you extrapolate this out to 24 or 30 inches, you are going to be left with a reading of around 100 par, which isn't enough imo if you want to grow light demanding SPS or clams near the bottom.

If you look at these posts:
Reef Central Online Community - View Single Post - What PAR readings to you keep your SPS in?
Reef Central Online Community - View Single Post - What PAR readings to you keep your SPS in? (questionably old bulbs, and the reflector on the left isn't the right reflector for the tank size so use the numbers on the right.

These are 250w MH's at depths of 24+ inches. One of the most important thing to keep in mind is that these readings are on bulbs that are 7-8 months old, so they are fairly conservative. You will notice that they range from about 700-800par at the surface, to 250-300 on the sand at a depth of ~24-27 inches. Compare this to the LED from the first link which is 3000 at the surface and a conservative guess of 100 at depth of 24-27 inches. Thus the 160w LED doesn't have the depth penetration of the 250w bulb, but "blows it away" in the shallower depths. This lack of depth penetration would be even more pronounced if it were compared to a 400w bulb, thus me saying they aren't comparable for a typical deepwater application that people use 400w mh's for, and are more comparable to 250w MH's. Maybe an 70-90 x 3w array would be comparable to 400w? Anyone else have some links with different LED fixture par measurements at depth?

Looking at those LED par numbers though makes me think they are more dangerous then originally though. While they lack the punch, the PAR levels in shallow water is enough to burn the crap out of an unacclimated coral. This must be what gives them their reputation for being "beasts."

 

[tat2z_21]

This maybe why a 250w 20k indicates less par, then a 250w 10k. I know that I have my Pheonix 14k and it read 180 PAR at the bottom of my tank, when my 10k almost had 250 PAR.

 

[tat2z_21]

Whith that being said the LEDs produce exactly the spectrum required for photosyntesis. Maybe this is why corals tend to burn up during acclimation periods. Too much of a goodthis is proven to bad in all things.

 

[trido]

Well said Jesse, I can see your doing a lot of investigating.

You are correct in only needing the actinic for a few hours a day. I however could tell the difference and preferred to run my VHO's all day. I did only run my two 60" T-5s on that tank for two hours a day with aquablue plus bulbs. Do you think maybe I had way too much light over that tank?
Jan was just over to my house for dinner and after seeing my new LED fixture with the shimmer, she may be jumping on the DIY wagon before I know it. The computer controller for a nice gentle blend into the different color spectrum's is a huge bonus with the LED's too. My tank gradually shifts from pure blue up to a near 10K and then back throughout the day.

 

[jezzeaepi]

Jan was just over to my house for dinner and after seeing my new LED fixture with the shimmer, she may be jumping on the DIY wagon before I know it. The computer controller for a nice gentle blend into the different color spectrum's is a huge bonus with the LED's too. My tank gradually shifts from pure blue up to a near 10K and then back throughout the day.

What is the controller that you use? I definitely want to see it in action.

 

[trido]

I built an arduino controller for about $50 that runs only my LED's.

 

[saltwaterfishes]

Radion arrived today. Color is crisp! I don't have a lot of flow in my frag tank right now, but this light gives out more shimmers than my current MH. Pre-programmed color setting has a wide range to choose from. Can't wait to plug it into the computer to customize it.

 

[mojoreef]

Ok its early and I have not had enough coffee so I apologize in advance if I do not explain this better, lol

Jesse you have to look at par in a slightly different manner then you are by just looking at par meter readings for different types of bulbs and bulb types. PAR (photosynthetic Active Radiation) is a term that was created for things on land and then has been adapted for marine organisms. Now land based organisms (plants and such) absorb light waves across the whole spectrum of PAR (or pretty darn close anyway) in Marine their a little more finicky and in corals they are even more particular. So when you are talking about corals doing the photosynthetic thing you have to look at it like this. Picture a oval shaped blob with two antenna (zoox) with in these zoox you have two primary absorbing pigments, One is Chlorophyll A (green) and the other is Peridinin (yellow) These two pigments absorb light photons primarily in the 420mn to the 490mn which to our eyes we call blue light. So with this we can safely say that light waves hitting a corals zoox that are in the zone of 420 to 490mn is the sweet spot??? for growth (or at least for the creation of products by photosynthesis for use by the coral as energy).

Ok so then we do some comparisons on the lighting sources. One thing we need to take note of is that Par meters such as Apogee have issues with reading light in the blue zone and that happens to be the one we want to talk about. So in testing it has been determined that you need to add 23.5% to your reading if the light source is in the blue zone. Ok then lets look at MH's here is a spectral chart for a bunch of 400 watt MH's

SOooooo when a par reading is taken off of any of these bulbs it is an accumulation of all the color waves from 400mn to 700mn because that is what PAR is. Vut do our little friends the zoox use all of the photons across this range of light waves for P??? nope they use the photons that primarily come from the 420-490 range so in terms of what is used and what is not it makes a big difference. So doing an unscientific look at this chart I think we could say that what ever the total PAR reading is, only about 50% of it is in the "Sweet Spot" so to say. Now lets look at the LEDS the same way.

Ok so as we can see the LEDS have a very narrow and very specific Light wave and those light beams happen to be all in the "Sweet Spot" . Thus we could determine that a PAR reading on these above bulbs is 100% in the zone most used by zoox in the photosynthetic process??? Or at least I can.

So if one takes the fact that apogee meter are 23.5% less in the blue zone (for which most commonly used bulbs are in) add that to the par reading and then compare it to the fact that MH's are only 50 % in that zone we get a little closer to being comparable or at least a little closer then we think by first glance of numbers that have not been qualified??


Ok we got pasted that so lets through in another little wrench into the mix?? lol going back to our zoox, the blob with two antenna. Now these antennas are the things that absorb light photons and they have a few things they can do. They can either absorb the photons and pass them down to the photosystem II reaction center in the zoox for further conversion in the photosystem I center which then creates the goodies for the coral, OR they can just fluorescence the photons away OR they can do what is called thermal De-excitation which is long for convert the light photon and burn it off as heat, and we all know what heat does inside a coral?? so anyway something to keep in mind when bombarding a coral with to much light from either light source?


anyway I need more coffee hope I didnt complicated it??


Mojo

 

[jezzeaepi]

Ok so as we can see the LEDS have a very narrow and very specific Light wave and those light beams happen to be all in the "Sweet Spot" . Thus we could determine that a PAR reading on these above bulbs is 100% in the zone most used by zoox in the photosynthetic process??? Or at least I can.

So if one takes the fact that apogee meter are 23.5% less in the blue zone (for which most commonly used bulbs are in) add that to the par reading and then compare it to the fact that MH's are only 50 % in that zone we get a little closer to being comparable or at least a little closer then we think by first glance of numbers that have not been qualified??

Thanks for the response Mojo.
So looking at the spectral plots for the LED, like you said it appears that both blue LED fall in the category of having all of their spectral output in the Sweet spot. The white LED though appears to suffer from the same issues that issues that MH suffer from, with 50% of its output falling outside of the 410-490 sweet spot. So, if a LED unit is composed of 50% white LED then 75% of the LED unit falls in the sweet spot. .75 X .235 = 17.6% under reporting of par numbers.

Similarly, if you had a MH bulb with significant blue spectrum(like a radium 20k, phoenix 14k, or reeflux 12k) with roughly 50% of the spectrum in the sweet spot, then it would be .50 X .235 = 11.8% under reporting of par numbers.

Then of course there is all the other factors that effect par like reflector choice, bulb age, how clean your bulb cover is, water clarity, turbidity, shadows, angle that you hold the light sensor, etc... I guess the only way to really get a good comparison is to do them myself, lol. Anyone have some LED units and some PAR meters they want to loan me? lol...

 

[oceanreefs]

Ok,this is some photos of the LED's on my RSM 650 hood.Phil

 

[dexter]

Cool thread

 

[mojoreef]

Theri are lots of par tests on both MH and LEDs on RF Jesse. Her is what it all kind of boils down for for me. With Mhs your going to get good enough to grow and color coral. 250s for shallwer and 400s for deeper, so it really just comes down to choosing a bulb color that you enjoy looking at. Growth will be slower and color more with some and visa versa. With Leds they do not have the spectral divercity that a MH does so I have found in designing and build units that you need to input that spectrum of colors yourself. So in the builds I use cool white, blue, red, green and violet, if you look at the spectral charts for these you will get a good mix of light photons that will grow the coral and also excite the various other pigments that we find pleasing when we look at them.

The way Leds are designed they need to use an optic, this will greatly enhance the intencity output bu in the same breath it narrows the beam. So as you have read prior par reading tend to drop off the map when you move farther left and right of that beam. Sooo to combat that you need to have multiple emitters covering a large surface area. You also need to raide the light fixture up a little higher to widen the beam of light the led puts out. You can also cross the beams to get a nicer blend of colors.

If you look at the fixture say like the radion (and most are the same anyway)

Your going to be able to say that the lights are tightly grouped so outside of that grouping your not going to be getting much in the way of par. With a diy unit you can spread out the emitters to cover that whole surface and thus you will get a larger area where the par is available. so kind of like this

Also the optics on the DIY are far superior to that of this unit. On my build we were getting readings of 500 par at 30 inches with 80 optics and that was with the power only turned to 40% output.

Mike

 

[mojoreef]

Dexter I am not sure if your talking about diy or not but I know Reedledlights sells these for 60 bucks their on their site.