Anyone Thinking of Dumping LEDS and going back to Halides

[lpsouth1978]

Woohoo!! A side by side test with the same water.

Can you frag the same corals so comparable colonies live under each light?

Maybe I will buy a couple of frags this weekend, weigh them, and place them on opposite sides of the tank. This should give a solid growth comparison, and my new camera will give a good color comparison.

Following I thought you had gotten out.

Nope, not out, just took a step back while trying to get all of the params under control. Also added dosers, removed biopellets and GFO, and got params DEAD stable.

 

[andrewbram]

Well good to see you again.

 

[lpsouth1978]

you know that quantity of light is what counts..
mh have a lumen efficiency of 70-115
LED's currently are exceding 160l/w and will most likely keep rising...where MH is "stuck"..for the most part:

And 10 3W emitters is usually not 30W of "lumens".

If you didn't replace MH's w/ at least 1/2W of real watts of LED's for 1 real watt of MH you really decreased your overall photon count.

LED's MAIN strength lies in maintenance, flexibility, and directionality..
minor strengths are energy savings and a few others..

Oh and a meaningless statement..

What are the diodes runnig at, and how many..

Good Question. The light has 456 3W Cree XP-E and XP-G diodes. All of the blues (420-450nm) and whites (Neutral) are running at 100% @1A, UV-not cree (405nm) are at 100% @750mA, and the red and green are running at 2.5% @750mA. The light is about 5" above the water surface with no lenses. We will be adding them to the 450nm blues, but the rest are on pucks that do not have a good lens option. We tried several lenses with horrible results, but we still get ~300 Par on the sand and more than 600 Par at the top coral.

 

[biecacka]

Lpsouth, I am looking forward to your side by side comparison. Question tho, are you usin a par meter? I only ask because you said that the halides look much brighter than the LEDs and that is normally the case but the par numbers can be close. LEDs look dim which is why many ppl fry their corals with LEDs.

Corey

 

[d2mini]

I only ask because you said that the halides look much brighter than the LEDs and that is normally the case but the par numbers can be close. LEDs look dim which is why many ppl fry their corals with LEDs.

Corey

Exactly. Think of an LED like the sun focused through a magnifying glass.
The light coming through wouldn't like up the room, but it will fry a bug or set a leaf on fire in seconds. LED are a very intense, pinpoint light source.

 

[lpsouth1978]

Lpsouth, I am looking forward to your side by side comparison. Question tho, are you usin a par meter? I only ask because you said that the halides look much brighter than the LEDs and that is normally the case but the par numbers can be close. LEDs look dim which is why many ppl fry their corals with LEDs.

Corey

I do have a PAR meter and found that I get about 300PAR on the sand and ~600PAR at the highest coral. We will see how the MH compares, though I do not have any readings yet.

Exactly. Think of an LED like the sun focused through a magnifying glass.
The light coming through wouldn't like up the room, but it will fry a bug or set a leaf on fire in seconds. LED are a very intense, pinpoint light source.

Fully agree, I have not tested the MH with the PAR meter yet. I am waiting for the 14K Phoenix to arrive (should be delivered today). The fact that we are not using any optics on the LED's, makes them much less likely to fry corals. I believe that the lenses that come on the LED's are 120 degree. If the new bulbs arrive today, I will get readings after work today, otherwise I will get them once they arrive.

 

[oreo57]

Thanks for answering my question btw.
Though you also didn't state height from led to your par measurements..

Anyways some pertinent (or not) data regarding the Phoenix MH:
http://reefkeeping.com/issues/2007-04/ac/index.php

The light output of the six Phoenix bulbs shows an initial decline over the first three to four months and then levels off at about 75% of their initial output. From these data I raise the question: “If a bulb is not replaced at six months, when it has lost 20% of its output, then why would we replace it at 12 months when its output has fallen only another 6%?” It may be more cost effective to plan the lamp number and placement based on 70-75% of the bulbs' initial output levels. Initially, we could shield or raise the lights and then gradually lower or unshield them over the first four months or so, when the intensity is at its highest but falls most quickly. Beyond six months the bulbs' light output remains fairly constant at about 75%, so only minor adjustments would be needed for at least a year. Doing this may considerably extend the bulbs' effective life.

LED's age as well.....

 

[jda]

Please don't think that frying coral has much to do with intensity or output. It is more likely wrong spectrum and PWM that causes the suffering. I grew frags outside under the sun in direct sunlight in 12" of water in Missouri and all the coral did was thrive... and nobody is getting close to that. Anybody think that they have more LED output than 4x 250W 10K bulbs on M80 over a standard 4x2 120G tank - coral only thrives.

I appreciate your post. Many have gone back to MH, or just switched, from LED (especially on larger tanks), but most disappear from the boards or are hardly ever heard from again. I think that if more of them posted, then it would help SPSers in the future.

 

[jda]

BTW - I used my 14K phoenix bulbs for 2 years... no issues. I give them away after that to a guy who uses them for a few more on his FOWLR.

I hope that you are running them on M80 HQI. You will get only good results on regular ballasts, where as they are spectacular on HQI.

 

[oreo57]

It is more likely wrong spectrum and PWM that causes the suffering.

Part one I can understand..
Part 2 PWM??? any data on that?

http://www.reefcentral.com/forums/showthread.php?t=2388963

 

[oreo57]

BTW - I used my 14K phoenix bulbs for 2 years... no issues. I give them away after that to a guy who uses them for a few more on his FOWLR.

I hope that you are running them on M80 HQI. You will get only good results on regular ballasts, where as they are spectacular on HQI.

Point was in a few months they lose 25% of their PAR. Stable after that.. It isn't an "issue" just a fact...
People sure seem to confuse the 2..........

 

[USC-fan]

Before long this wont even be a option. Trying to find good MH reflector now and is kinda shocking how little selection there is any more....

Making me second guess MH to be honest.

 

[karimwassef]

Really? I haven't had that problem. The good ones are still around and very cost effective too.

 

[jda]

...so Coralvue Lumenarc Mini & Large, the half of a dozen or so offered by Hamilton are not enough?

Why do people keep on thinking that a company that SUPPORTS THE REEFING HOBBY will quit making products that people buy? It isn't like Hamilton is selling Cozumel Sun reflectors to light street corners, or that a Lumenarc Mini lights warehouses. They make them, and make profit, because people in this very hobby want them and will pay for them. They will always be around until there is a better alternative... and if that day should ever come (not likely with the current bunch of stuff on the market), then nobody will care anyway. URI still makes VHO bulbs. Phoenix figured out that LED were not going anywhere and started to make their bulbs again. Hamilton is doing well. The bigger threat to reefing companies is IP theft from China, rather than new tech.

As for the PWM - I have no facts, just observations and supposition from a hobbyist. I will say this, JP has had more success with his reef tanks than Pacific Sun has had with all of their "facts..." again, just an observation.

 

[Nano sapiens]

Please don't think that frying coral has much to do with intensity or output. It is more likely wrong spectrum and PWM that causes the suffering. I grew frags outside under the sun in direct sunlight in 12" of water in Missouri and all the coral did was thrive... and nobody is getting close to that. Anybody think that they have more LED output than 4x 250W 10K bulbs on M80 over a standard 4x2 120G tank - coral only thrives.

Addressing some of these points:

Incorrect Spectrum: The spectrum can be 'wrong' if it doesn't mimic the light field found at the depth that the coral is comfortable at. LED arrays tend to be heavy on the blue since even 'white' LEDs are blues with a phosphor coating to produce additonal hues. Having so much blue, they can over stimulate photosythesis (high PUR value) beyond what the coral can tolerate while still appearing relatively dim to our eyes.

PWM (Pulse Width Modulation): I have built LED arrays with Inventronics direct drivers and Meanwell drivers (PWM) over the same tank/corals and I have not noted any differences in the way that coral respond (including SPS). Certainly no 'distress' due to PWM.

Coral under Sunlight (high PAR): PAR from direct mid day sunlight is typically quite high since it is a true 'full spectrum' source. Since PAR is the equivalent of all visible wavelengths between 400nm and 700nm, that's to be expected. However, much of the 'full spectrum' is not utilized (or weakly utilized) by the coral zooxanthellae. One can have a high PUR LED array (violet/blue) that will provide similar photosynthetic stimulus as full sunlight at a particular water depth, but it will have a much lower PAR value and appear 'dim'.

 

[oreo57]

They make them, and make profit, because people in this very hobby want them and will pay for them. They will always be around until there is a better alternative..

Actually in marketing that is rarely true.. They will be around only as long as a "sufficient" profit is make-able..or until a higher profit usable product is introduced..
business is in business FOR business.. not hobbies..
for awhile you end up w/ some "niche" manuf. that will make it out of, maybe even love, but it will not be a multi-supplier market..
Or one Chinese factory supplies all the product to "the world" under a few different names. "oh wait" that already happens..

 

[biecacka]

So am I reading this correct, "If I have the proper spectrum on an LED unit, I can run it full blast overtop one of my corals in 24 inches of water with no concern of frying it?"
I think that is one major flaw with LED's we don't have any consistent information. Everywhere I turn there are horrors stories of LED failures.

Corey

 

[oreo57]

So am I reading this correct, "If I have the proper spectrum on an LED unit, I can run it full blast overtop one of my corals in 24 inches of water with no concern of frying it?"
I think that is one major flaw with LED's we don't have any consistent information. Everywhere I turn there are horrors stories of LED failures.

Corey

not quite that simple.. What if you are 3rd generation cave dweller and suddenly thrust into the noon sun? You'd fry too..

 

[USC-fan]

...so Coralvue Lumenarc Mini & Large, the half of a dozen or so offered by Hamilton are not enough?

Why do people keep on thinking that a company that SUPPORTS THE REEFING HOBBY will quit making products that people buy? It isn't like Hamilton is selling Cozumel Sun reflectors to light street corners, or that a Lumenarc Mini lights warehouses. They make them, and make profit, because people in this very hobby want them and will pay for them. They will always be around until there is a better alternative... and if that day should ever come (not likely with the current bunch of stuff on the market), then nobody will care anyway. URI still makes VHO bulbs. Phoenix figured out that LED were not going anywhere and started to make their bulbs again. Hamilton is doing well. The bigger threat to reefing companies is IP theft from China, rather than new tech.

As for the PWM - I have no facts, just observations and supposition from a hobbyist. I will say this, JP has had more success with his reef tanks than Pacific Sun has had with all of their "facts..." again, just an observation.

Thanks for proving my point. Those are not even made any more. Sunlight supply stop selling MH product to reefing also.

Trying to find a short but wide reflector is impossible. Just trying to find any DE reflector is upsetting.

Both those companes list just one DE reflector. Cayman Sun - 250 Watt HQI Reflector and Lumen Bright Mini Metal Halide DE Pendant.

On marine deport, aquacave and bulkreef supply only list a single DE reflector. I cannot even find the Lumen bright DE reflector for sell through google.

So we have a single DE reflector that will not work for me because its too much of a spotlight. I wanted to run Phoenix 14k. Did they start making the single end version again? Really love the color of the 14k with HQi m80 ballast.

Now you see the problem?

 

[jda]

Which one did they used to make that you would be happy with? Was there one? I have 30 or 40 in my stash and I can take a look. DE does suck more than SE, that is for sure. The hard thing about DE in larger reflectors is that the glass is super important.