leds and LPS color changes

[TropTrea]

really missing the pinks and the reds. Any benefit to add a magenta stunner? Not sure what the wavelenth is or is it just a red (white bulb). The AI is a great light but there is acolor hole that needs to be filled.

You need to watch what kind of magenta stunner.

magenta can be a combo of blue and red light.

Or it can be light under 430nm since this light stimulate ones night vision with visual purple in one eyes.

If your looking to emphisize the reflective reds then go with the red and blue combination, for florescent reds it realy depends on the particular coral and what the exciting frequency is of its particular chemicals that floresce.

 

[TropTrea]

Over in another thread,



Here's Apogee's response graph:

Since most "white" LEDs are actually blue LEDs with a white phosphor (called "blue-driven white"), LEDs have a huge spike around the 450nm graph tick. As gbru316 said, that means the Apogee quantum meter under-counts the LED's PUR.


this is why I personly question the value of some pof the PAR readings. If you look at the chart you see the sensitivity of the meter is basicly opposite of what corlas need. Corals need a lot of blue light that do not give an accurate reading on a PAr meter. This is why some LED fixture manufacturers use a lot of white bulbs namely to push the PAR numbers from the meter up while thay may be lacking an acceptable amount of blue light for the corals.

So can the problem be people using a quantum/PAR meter, seeing a false/lower reading than expected due to the nature of the sensor, bumping up the LED output and then over-exposing their corals?

 

[parrthed]

I picked this Brain up a couple weeks ago. It was under 12k reeflux 250w in the store and had been there for a few months. It was a nice teal green and very fleshy so I had to have it.

I wanted to acclimate it to my AI Sols so I put it under an overhang and left it there. Well, I was moving it out today and noticed that the parts that were exposed to direct LED were changing to a red striped polyp. The brain appears very healthy and eats regularly. I hope this isnt a problem, maybe just a cool morph under LEDs

Top ( the entire brain was this teal color, you can see some of the red along the edge)

Side that was fully exposed

 

[victor escobar]

It seems that the information provided in this post can be usefull and therefore I reopen it

 

[TropTrea]

One thing that we are missing it that have been over 100 florescent pigment isolated into different corals. Most if not all corals have several different pigments. Each florescent pigment requires a specific wave lenght to activate it florescence and in return emits light a a different specific frequency. The ratios of the florescent chemicals in the cors is very dependent upon the amount and wave lenght of light the coral is getting. If it does not receive light at a frequency needed by a particular pigment this pigment will slowy start diminishing in the coral. Siularly if another pigment is getting enough light it will flourish within the coral. There have been several studies done on this and they all proved that it is an important factor in why corals of the same species only under different light appear to be colored differently even though they are healthy. This can also be seen in nature where the same coral only at different depts of of the ocean may be considerably diferently colored.

Now on the Par meters I'm personally thinking they are less and less inportant. The light in the ocean is very heavy in the blue spectrum and very thin in the red spectrum. Yet when we use a PAR meter it is much more sensative to red light than it is to blue light. Actualy the opposite to what is ideal in the reef tank.

 

[victor escobar]

Hel Troptree.Thanks for the last post.

One question: I am not so concerened about the colors of the corals (even if as everybody the most flourescent the better for the view of our tanks), my problem is about the health of the corals, I am not sure about the link between the quantity, quality of the pigments and the health of the corals (geeting enough food from the light.- zooxantelae), In fact my feeling is that there is a link though not in all cases.

For example in my modest tank red lobophyllia change the colors (different pigments excited) but at the same time they slowly get weaker (2.5 years already getting weaker) and some of them at the end die.


What is your view on that?

 

[TropTrea]

As far as the healt of corals are concerned you have the photosynthetic chemocals that basicly convert light CO2, and Water to sugar which the corals use for growth. In slat water corals the most frequent of these are Chlorophyl A, Chlorophyl B, and Beta Carotene. Each of these have there own frequencies they need the light to be at to most effeciently cause this process. This light comes either directly or through the florescense of other chemicals.

Chlorophyll A needs light between 400 and 450 nm as well as between 670 and 680 nm. But it's most important peak is around 430 nm.

Chlorophyll B needs light mainly between 450 and 480 nm. With its peak need around 455 nm.

Beta Carotene can use light between 400 and 500 nm with its peak need at 450 to 480 nm.

There are other chemicals that are photosynthetic however most of these need light in other areas like Phycoerythrin at 560 and Phycocyanin 620 nm. Since most of the light is filtered out as one goes deeper in the ocean these chemicals are either found only in shallow water corals or receive this light through orange and red florescent chemicals in the corals.

Overall the basic idea is to get light in the 420nm to 480nm range to the corals for growth. The most needed light being around 455nm (peak of the Royal Blue LEDS') Then suplement with neutral white lighting just enough to make it pleasing to the eye. You realy do need much red light above 500 nm and the little that is needed will be well compensated for with the whites.

where a 100% LED system has it short commings is filling in that needed gap between 420 and 440 nm. There are very few LED's available in these frequencies at reasonable prices from the top quality manufacturers. Some of the ones that are available have broader spectrums and emit light as low as 380 nm which is the edge of harmfull on the UV end of the spectrum.

 

[Nano sapiens]

Excellent read. I noticed a lot of comments regarding reds turning into oranges. I experienced this phenomenon in an Acan, both with a 10K/Actinic T5 combo and with Similar spectrum LED strips (Ecoxotic Stunners). I suspected that something in the light spectrum was missing, so I added a 10K/Magenta strip and noticed a much improved color shift towards the red.

Here is the original very red Acan rescue frag (kept under full spectrum T5s at the LFS):

Orange phase under T5s/LEDs (top-most Acan in this pic):

Red is better, but still not what it could be (lower Acan mini-colony):

It's difficult to say if the increase in the 'Blue' wavelengths peaks in the 10k/magenta helped the red pigment to redevelop or whether the 'warmer' spectrum (peak of around 650) of the Magenta has helped, or possibly a combination of both?