Confuse about intensity and spectrum

[Nano sapiens]

So you don't put a meter on your tank.

I think we should agree as we all have more access to the information that this is actually bad for many corals.
Because it doesnt look like this.

Many of our corals come from much shallower waters than the typical provides and manufacturers(some) are noticing and adding the other appropriate colors.
In a side by side test done by Dana R the greatest growth success was from using this spectrum


Youll have to explain that one. I thought the point was to replicate natural sources.
And many don't understand that the preference for blue in photosynthesis has evolved because of the color of the sky

Replicating the natural light source yes and the consideration for the aquarist should be "At what depth?" Since most of us don't know the depth of collection of all our corals, we make the relatively safe assumption that they came from easy to collect, 'shallow water' reef environments. Running with that assumption, even in shallower depths, much of the red and some yellow and orange is lost compared to sunlight at the surface. These 'warmer' colors are poorly utilized for photosynthesis, but what some of them can do is stimulate the production of coral non-fluorescent pigments. The manufacturers are catching on to this as well as the fact that the mis-nomer 'Full Spectrum' (only the Sun is truly 'Full Spectrum') has a nice ring, or is that 'ca-ching'?

My understanding is that the corals zooxanthellae have evolved to utilize the violet/blue spectrums since these are most abundant at depth in the ocean. This adaptation allows many corals/zooxanthellae to exist within a range of depth (sometimes quite broad). If they had to rely on the warmer colors present in shallower waters for most of their photosynthesis, they'd be much more depth restricted.

Supplying the correct spectrum to a coral is great, but if you are doing it from a tiny single point light so only the top of the coral gets light, why did you spend so much time researching spectrum so you now only use the top half of it. . Look at all the lighting guides on MH use. the reflector was not there just to increase the light on the subject, but to get spread over the entire coral. We now commonly ignore that.
Most people would be surprised to know the best way to improve you PAR is to get rid of the black background and use blue(yes thats why they did it not aesthetics) or white(gotta choose that white carefully of course )
And corals come from much shallower waters than the "typical" led provides but it looks cool. And many in the hobby do understand this.

Good point about coverage which is especially relavent to LEDs. European and some Asiam manufacturers produce arrays that cover the aquarium surface (or nearly so) using a great many LEDs run at lower wattages to correct the common problems you've addressed concerning a concentrated light source.

 

[Nano sapiens]

^^ 'These 'warmer' colors are poorly utilized for photosynthesis'

I should amend this to say that Chlorophyll A has a peak in the red wavelengths aroun 660nm, but coral zooxanthellae are primarily adapated to using violet and blue wavelengths.

 

[dacianb]

I run a small test in the lab. Yes, I have access at light measurement tools worth more than a Ferrari and basically designing and measuring lights is my job since 20 years.
Below are measured 4 different LEDs at a distance of 1.5meters, all powered at same current (700 mA) and junction temperature maintained at 30°C (all equipments used are calibrated twice / year and procedures used for tests are according to CIE standards).

As you can see there is no correlation at all between PAR, Lux and W. Measuring PARs in Lux is similar to measuring distance in kilograms. Even further, PAR as parameter is weak for the corals, as you see, red light have highest par, but we all know that is not used by corals

This is a print screen of measurement interface of the spectrometer (cold white LED in this case). PAR and more details are exported as excel files and do not appear in this screen (can send them if interested)

I didnt say I not measured my lights. I measured them more detailed like above - I know exactly what each led and channels is doing at what distance. But didnt made it ON the tank, but in the lab.
By not collimating leds (use the primary optics only) and placing few leds above the tank, corals are illuminated from everywhere, not only from top.

And, as conclusion, in my opinion a healthy coral is the one that have beautiful colors and all day long extensions - I dont care if they grow half the speed of others, as long as they look healthy.

 

[dacianb]

PS - sorry I didnt had any deep blue / violet near me to add them to this table, but in this case the difference between par/w/lx should be even higher and making more a non-sense.

 

[ReefLEDLights]

With LEDs it becomes more complex.

Specific Binning can produce better results.

The Cree Cool White has 28 different colour variations...Choosing a warmer or more red Bin may not be the best solution.

I've seen the best results in a Reef Tank using Cree Cool White LEDs with a cooler Bin Mixed with plenty of 455-410nm LEDs .

A couple Red 660nm May help depending on the Coral.

Not all LED Companies Bin their LEDs

Bill

 

[dacianb]

With LEDs it becomes more complex.

Specific Binning can produce better results.

The Cree Cool White has 28 different colour variations...Choosing a warmer or more red Bin may not be the best solution.

I've seen the best results in a Reef Tank using Cree Cool White LEDs with a cooler Bin Mixed with plenty of 455-410nm LEDs .

A couple Red 660nm May help depending on the Coral.

Not all LED Companies Bin their LEDs

Bill

They will do if will pay for it. Unbined leds are half price of bined ones [emoji1]

 

[saltyfilmfolks]

Measuring PARs in Lux is similar to measuring distance in kilograms.

Im glad you stayed in the conversation. I too have ferraris at work. I wish they paid better so I could have one at home.

I am not saying Lux is good for reading par. It is not. But to be fair I would say It is a more fair comparison to say it is like using an API test kit compared to A Salifert or hanna. Or, if you like a wind sock to measure wind speed. A lux meter is a very Basic tool. It measures light intensity. Only. I will not argue that. Intensity (however measured) is a factor of par.

What I do argue is the average reef keeper can successfully say how much light he has, and if he has enough light for his corals.
By telling the average person that a lux meter is a useless tool on this website with so much combined knowledge is unfair. It leaves MANY out of the game. It makes the science inaccessible.
It is a teacher telling a student he cant learn.

Most people dont know you can grow corals under a phillips Par 38. You can.

By saying a person needs a very expensive meter for his corals limits access to the hobby. Most people who post questions on light here simply have not enough intensity.
They are guessing by eye or internet how much or what percentage the dial should be at.
I firmly believe a lux meter can fix that problem.

I think it also the beginning of teaching about intensity and spectrum and furthering learning about the the hobby and light.
I will also help people make wiser choices when purchasing a fixture, because when you buy a bad one and everything dies and its a struggle, they quit very quickly.

Most of the lighting fixtures sold here and are most popular have 2 dimmer channels. White and blue.

Here is the method I use for beginners or average people:
Measure the lux at the top of the water on the white chanel at its max, write it down. Measure the minimum, write it down.
Measure the lux at the top of the water on the blue chanel at its max, write it down. Measure the minimum, write it down.
A fixture that produces less than 5,000-10,000 lux combined will probably not grow coral well especially if you have a deep tank.
20,000 combined is probably fine for an 18' deep tank if the fixture has a good spectrum.
If your light reaches 100,000 lux singly or combined it is going to be WAY too much for your coral.
Take your Lux meter to the store and ask to test the light so you dont get fooled.

What is wrong with this method or advice? Too simple? it works though.

corals are illuminated from everywhere, not only from top.

This was not directed at you. It is the current Fashion with lights here in the states.

Fashion speed and style are a bit of a disease here where it relates to coral and aquaria. The tiny single source all blue all the time tank.
But to those who honestly just want a nice tank some corals understanding the spectrum mostny corals want can be pretty east without asking the hobbyist to be as well equipt and obsessive as we are

It is refreshing that we all agree so far that different coral need different spectrum. So many don't yet understand that. And many manufacturers wont say that. On light for all corals. Thats amerika"

I've seen the best results in a Reef Tank using Cree Cool White LEDs with a cooler Bin Mixed with plenty of 455-410nm LEDs .

A couple Red 660nm May help depending on the Coral.

Not all LED Companies Bin their LEDs

Bill

Thank you for chiming in bill. You do great work. If I may I'd like to call you out a bit.
"I've done numerous measurements using a PAR Meter and Lux Meter. MH, T5 & LED. I cannot say the comparison is linear buts its awfully close.
A Lux meter comparison should work fine." Bill ReefLedLights.com

Particularly good for acclimation IMO, as now you have a number to start at.

would put forward that there is a correction factor that needs to be used for reading the high 450nm range with a hand held lux meter. (as we both know thats the first thing a par meter does using optics and filters.).
I would assume you would be able to calculate that correction factor rather quickly. 10%, 30% 60%?
That actually does make it rather simple, and is likely 100% Correct. Id wager the percentage is also negligible as well.

I would encourage you with a lab to figure this out. ^^^^^^^^ Then I (and you) can tell people how to set their 2 or 3 Chanel dimmer with a simple tool.

Why? To encourage learning. Random act of Kindness. And then when they borrow a par meter they know what they are looking at. And now when they look at Bills lights they understand what hes talking about.
(And no more endless debate threads)

@reefwiser


The aim of argument, or of discussion, should not be victory, but progress."

Yea, I could be wrong. But Id appreciate the chance to progress as well.

 

[dacianb]

Thats a reply. Thanks a lot and wow, thanks you are not one of those who knows the secret of univers because red a web article. Honestly i measure lights for fun not because of corals. I have very powerfull lights but keep them on low. Then i increase slightly and see reaction of corals. They like it? A bit more and so on. I have hammers next to sps and looking awsome. Hammers on sand too and great looking. Next will be to put sps on sand and see. I am using Osram squares for deep blue- real 450 nm, square neutral whites with high cri, oslon signals for blue and cyan and luxeon uvs. Now i am building a new light with some 680-730 nm too in. All without any optics, kept at 40deg celsius and at 1 inch from water level. All energy is in tank spreaded uniform and nice. I have a rimless tank with almost invisible lights.

 

[saltyfilmfolks]

Yea I hate seeing the lights.
Some of the reefs you never see on the boards are combined SPS and Zoa with softies. Blows that myth out of the water.
A friend of mine is older and quite wise. He imports corals direct (san Diego) and Yea my zoas come with some types of SPS.

Honestly, Im in the hobby and the boards to learn and sometimes teach what I have learned.

Then i increase slightly and see reaction of corals. They like it? A bit more and so on.

Par or Lux, your still gonna learn something from an animal with no brain.
Happy reefing.

 

[puffy127]

Would a LUX meter work for comparing the light intensity for 2 different lights? I have a coral QT under one brand of LEDs and my DT under a different brand of LEDs. I would like to know how comparable the two are so that I know how to light acclimate the corals when I transfer them to the DT. But then how does one account for differing depths (on a frag rack close to the LEDs in the QT) vs on the sandbed in the QT. Also how do you account for distance from the center of the LED (depthwise)?

 

[saltyfilmfolks]

Yes. It measures only intensity. And a big reason I advocate them. It compares intensity between 2 sources.

But then how does one account for differing depths

Estimation.
Sadly the dont make the Lux meter with underwater probe anymore.
Now with LEDS hold the meter farther away inches, for a more accurate reading. Nearly impossible to do with the app BTW.(how the camera works)

Once you have a lux meter in your hand its much easier to understand. you can measure desk lamps. Sounds silly but its part of the learning curve with the meter. Probably take you 1 min to use it(push button), 20 min to understand it(take farther away from desk lamp), a day or so really get it on how best to use it on the tank.

One thing to note is color specifically blue. If one tank is 20k and one is 10k (unlikely these days LOL) you have a higher mix of the blue spectrum. Once you have the meter and a 2 channel mix knobs youll be able to test the intensity of both and combined. some corals dont respond well to high blues.

 

[puffy127]

Your mentioning of measuring desk lamps triggering this question - can I use the ambient light monitoring (measures lux) feature from my ColorMunki display calibration device instead of a lux meter? http://www.xritephoto.com/ph_product_overview.aspx?id=1513

 

[saltyfilmfolks]

Your mentioning of measuring desk lamps triggering this question - can I use the ambient light monitoring (measures lux) feature from my ColorMunki display calibration device instead of a lux meter? http://www.xritephoto.com/ph_product_overview.aspx?id=1513

lol
Personally id try out the app or spend the $15.
I have no idea how that would do over a tank
but being a glutton for punishment my self, id try it.
then spend the $15

 

[saltyfilmfolks]

yea that was a good one