Par from T5 vs par from led

[saltyfilmfolks]

The Version 1 and Version 2 of the ReefBreeders Photon. You might have to go RC since the V1 is not very new, but everybody will caution folks to keep the whites under 30-40%.

Ah, got it! Yea. Old AI had the same problems

 

[oreo54]

V1 RB and even the V2 can burn coral... mostly SPS. You can search on this issue. You are right to keep the whites below 30%, IMO. This is a quality thing, not a quantity thing.

In general, I only ever hear of it with white LED spectrum and SPS, but mostly acropora.

Question for you.. for those that found white light to be detrimental and turned it down did they raise the blue output an equal amount to what was cut?
And were the whites high K whites (as expected really)
See I have this theory, since the "white thing" and SPS makes little sense to be honest.
White LEd's are a subset of "daylight" and as such pretty neutral on its own.

See the enigma does present a "simple" solution (usually a bad start but I'll continue) that wouldn't really be noticed because of common wisdom.
Now bear w/ me and this may be way off track but would answer some of these riddles..

High K white LED's are mostly blue w/ a very low percentage of "not blue" and then you have pure blue on the other channel.
In effect, and based on the natural world a high blue light would signal "deep water" to the corals and zooxanthellae.
This creates a situation where they "drop their guard" so to speak and do not "adapt" from low light systems to high light system.

So they "overheat"creating too much O2 ect.

The bulbs you use generally do not do this because of a higher proportion of "not blue" light..
Point is you may overcome this using a lower K white LED with more "not blue" content.
Activating the systems to shunt excess light.

Call it a working hypothesis and would be shot down if one using blue/white LED had the headroom to dim the white and increase the blue proportionally and find a
different effect.

Point is it's not white but the type of white (quality of white if you must)
I get that LEd's do affect "some" corals much differently (minor color changes aside) than would be expected by its intensity and really blaming "hot spots" doesn't seem conclusive not "exactly" quality of PAR. find the use of the term different to be more neutral..

And again, not really talking quality of the corals but survival here..
Quality comes later.

JUST turning whites down to 35% (losing 35% of your "par") just doesn't sit well.
It's possible (and have no proof either way) that turning the blues down to 35% would accomplish the same thing..
doing that would be common sense counter-intuitive..
Just for fun:

http://www.reefcentral.com/forums/showthread.php?t=2505162

 

[jda]

I do not know the specific answer in the frame that you are asking. Most of the RB V1 and V2 experts on RC (ron the reefman) run two blue channels at 60-70% blues and keep the whites at 30, or so, if that helps. The diodes were cool white or daylight or something early on (helpful, right?). The ones in the current fixture are Cree XP-E 5500 5w - I have no idea about the lenses.

I agree that it is a quality thing. I have no issue with white light from T5s or MH. Years ago, there was a spectrum analysis of the white diode and it had peaks many times higher than a 6500k bulb or daylight... like maybe 15x or 20x... and somebody overlaid a 6500k bulb over it to show the wasted and damaging spectrum. I can see this graphic in my head, but I have no idea where to find it. Of course, a PAR meter would read all of this as positive since it is between 44o and 680nm. If you remember back to those times, this is what led to the blended diode white light approach and "upgrade." LED burn was a real issue, that kinda got solved on some newer fixtures.

I do not know about the rest of it. It is possible - we know nothing about this other than "what mostly works" and "what mostly does not," and even some of that is in the eye of the beholder. In the end, people need to run lights over their tanks and turning the whites down will work. I like to go a bit farther and explain some things so that they know what they are getting into for the next purchase, but I am kinda getting sick of the PMs that I get on both boards for my apparent lack-of-fact hatred of LEDs (the facts being the stuff that the manufacturers publish).

Ultimately, I do not really care... yet. I do pay attention to LEDs and light discussion because if/when they ever become a viable replacement to my MH for my acropora, I will want to move to them. Every year is the same thing... only it has been a decade now. I also want people to have nice acropora so that I have people to trade with.

Keep in mind that a lot of people do not have very new lights... the older Photons, AI, Radions, Sols are still out there in good numbers which is why I always ask about whites when people post of burnt corals.

 

[oreo54]

I'd suspect almost all the old lights had 10000K or higher whites

The ones in the current fixture are Cree XP-E 5500 5w

If that is true and they don't have the same "issues" as the older style lights it supports my "theory"..

too much blue not enough "non-blue"...

5000k (not CREE just for example):

THAT is a huge difference really..
ROUGH composite for reference..
RED starts at 620..

10000k mh for comparison:

 

[Big E]

White LEDs up too high was always a problem from day one............not from a par perspective. I told people that 5+ years ago as they would try to get the same ambient look they would with bulbs.

It's what basically led to the windex look in LED tanks.........it was the only way not to fry acros.

Early on it was a big issue when the ratio of blues to whites was 1-1 or 2-1. Now that it's more of a 3-1 or 4-1 if you include violets it's not as much of a problem.

There is also much better control now.........it's common to be able to control each color.

This is also why T5 mixed with LEDs can work good or help as you can turn the whites down on the LEDs.

I addressed some of this on post 26 here--
http://reefcentral.com/forums/showthread.php?t=2198810&page=2

On another note you can do this with any massive or high spike the corals don't like regardless of color. The spectral distribution is skewed to such a degree that the acropora are damaged. This was never possible with bulbs.

 

[TexasTodd]

Thank you all three of you. This is very helpful and kind of what I suspected after using the PAR meter. Living in San Antonio, heat is a HUGE issue so there's a real draw to the LED. I've run all the way up to 1000w halides in the past with no issues. This confirms the need to upgrade lights as soon as possible. I've already had a LFS offer to give me a trade-in on the RB V1 which surprised me, but is great.

 

[oreo54]

On another note you can do this with any massive or high spike the corals don't like regardless of color. The spectral distribution is skewed to such a degree that the acropora are damaged. This was never possible with bulbs.

Only spike in white LEDs esp high K whites is royal blue.........

 

[cpark645]

With T5's its evenly disbursed par, with leds, they use reflectors that focus the light down and can cause par hot spots.
So here is an example of T5 par coverage from the Aquatic Life T5 fixture

And here is a graph for a Radion G4 Pro

As you can see, the leds have a pretty good hot spot right under the fixture whereas the T5's have an even blanket of par coverage. Also with LEDs there is alot more shimmer, which causes quick bursts of high par to corals, whereas T5's dont give off alot of shimmer so the corals get continuous par amounts with little fluctuation.
I hope this helps with your question

Is this 6 inches from the bottom of the tank or top of the tank?

 

[Crabs McJones]

Is this 6 inches from the bottom of the tank or top of the tank?

This par chart is with the light 8" off the waters surface 6" under the water in the tank.

 

[cpark645]

Wow, 4 T5 bulbs don't put out as much PAR as I thought..

So If I have a T5/radion hybrid, I'm assuming it would be mathematically correct to just add these numbers up?

 

[madweazl]

Wow, 4 T5 bulbs don't put out as much PAR as I thought..

So If I have a T5/radion hybrid, I'm assuming it would be mathematically correct to just add these numbers up?

I got 130 PAR from two 54w ATI Blue+ 8" below the surface measured with an Apogee MQ-500 last year. I should have the PAR meter back in a couple weeks and will measure the 48 AquaticLife with and without the LEDs on.

Edit: I think that was actually with a Blue+ and a Coral+.

 

[jda]

Lets don't forget that the Aquatic Life is not made to be a PAR monster with T5s. It is a solution for people who are serving two masters. You cannot expect a hybrid solution to be a better performer - it was made so that people have options and versatility... you sacrifice something for this.

On an ATI Fixture, you can get 80-100 PAR per bulb 6" under the water... but it is made to just kick butt is this world only. When you go all-in you can kick more butt.

 

[dz6t]

If we hit only the nm corals use , the tank would look pink. (Red and blue )

Not a promo , but look at where the cloryphyl and carotenoids are.

The kessil logic thing is to make sure you can grow corals no matter where it’s set. It’s just more blue or less.

I run my lights at a 1:1 white blue. Most of the useful stuff is in the blue end , yes, but I like that me red fish and red corals look red. You need red to reflect red so we can see red.

Fortunately kessil doesn’t post any of thier spectrum or par or anything else , so we don’t know how much green ( middle green) they use. They need some as other wise it would be blue ish pink (they do use less red than some )

Make sense?

No, it does not make sense.
The graph you posted from one of the led manufacturer is wrong information. Coral photosynthesis action graph is different than plants on land.

 

[oreo54]

No, it does not make sense.
The graph you posted from one of the led manufacturer is wrong information. Coral photosynthesis action graph is different than plants on land.

Actually it is not that different.. when considering photosynthesis..
http://jeb.biologists.org/content/206/22/4041

Need to keep in mind both are done w/ extracts and it is different (for both) in actual tissue BUT the main absorbances still apply..

 

[madweazl]

Lets don't forget that the Aquatic Life is not made to be a PAR monster with T5s. It is a solution for people who are serving two masters. You cannot expect a hybrid solution to be a better performer - it was made so that people have options and versatility... you sacrifice something for this.

On an ATI Fixture, you can get 80-100 PAR per bulb 6" under the water... but it is made to just kick *** is this world only. When you go all-in you can kick more ***.

The AquaticLife reflectors leave a lot to be desired, that is for sure.

 

[alton]

For what it is worth on comparing PAR from LED to MH. I traded corals for a Marineland Reef Capable LED when they first came out. I set up a test tank and I added a a few corals to see how well it would do? After a couple days it burned a birdsnest coral. That is when I performed some test. First of all the leds where like spot lights with a very narrow beam. The PAR was only 200 at the top of the tank but my foot candle meter showed 4,000 which is comparable to a 400w MH. If you changed to LUX it would be around 43,000+? On my MH at the time there was only about a 25% difference in readings between PAR and Foot Candles. So it wasn't too much PAR, but just too much worthless light that burned the coral. Today's Leds are so better at having a wider pattern while having a much wider spectrum, therefore showing greater numbers on a standard PAR meter. I remember frying some corals once when I tested a 10K MH (advertised as 14K) lamp while replacing a 20K radium lamp (which is more like a 14K+ and are comparable to a Phoenix 14K, both in PAR and looks).

 

[dz6t]

Actually it is not that different.. when considering photosynthesis..
http://jeb.biologists.org/content/206/22/4041

Need to keep in mind both are done w/ extracts and it is different (for both) in actual tissue BUT the main absorbances still apply..

Coral are capable to manipulate light wavelengths via its protein.

 

[BoomCorals]

The AquaticLife reflectors leave a lot to be desired, that is for sure.

I agree. It’s the one shortcoming in my opinion.

 

[dz6t]

Have you done any comparison between ATI and aquaticlife reflectors?

 

[BoomCorals]

Have you done any comparison between ATI and aquaticlife reflectors?

Yes. 4 bulb ATI crushes 4 bulb aquatic life in PAR. ATI 4 bulb gets me about double the PAR if I recall.