Färgtemp åt koraller

[aerie]

Bara ett litet intressant utdrag ur en tråd på RC,tyckte det var läsvärt:

http://www.reefcentral.com/vbulletin/showthread.php?threadid=24579&highlight=anemone+feed

Dr. R Shiemek:

Hi Folks,

Well, thanks for your opinions. Opinions are nice, everybody needs a few. The various opinions and thoughts circulating about the light needs of marine photosynthetic organism as generally expressed on this and other forums are a strange form of fiction. As expressed here, they are typical. They have just enough science in them to be called science fiction, but the plots of the stories are thin, and colored a lot.

Unfortunately these opinions run foul of biological fact.

First, Sure - the algae in corals have accessory pigments that allow them to get some energy from the light of that reaches them at various depths.

Are these pigments effective? Well sure, sorta. They help. But consider what they do. They DO NOT do photosynthesis. They collect some electromagnetic energy and pass it in a number of different ways to the photosynthetic pathways. They are not particularly efficient at doing this, but they are better than nothing.

Ask yourself the question, “Why is a coral down at a depth where it needs accessory pigments?” Do you think this is a good place to be.

I will bet some of you answered “Yes.”

Think again. The food and the light are closer to the surface. The corals at these lower depths are there because they are forced there, either by competition, by predation, or by some other factor. Natural selection has, in these cases, favored some sort of processes to assist the organism to stay alive and maybe reproduce.

Now, would any of these organisms do better in shallow water? Damn straight they would. Why? Because in shallow water they get more food and they get more light. And generally, the closer to the surface they get (within the boundary of UV lethality), the better.

Why???????

As far as light is concerned, it is because they get more light. They get better light, it isn’t the damned dim low powered blue light of the depths, it is real honest light. The ability to handle blue light is a bail out for them, it is not an optimal way to go.

Every coral that has been tested will do better in full spectrum daylight than in any other light. I believe it was Casey Stengel who said, “You could look it up.”

And you ought to.

Instead of wasting your time and energy worrying about the flavor of the light popsicle you let your animals lick, you should be concerned about getting them enough energy. Light is an important part of that, but they need to be well fed as well. Food is essential if the zooxanthellae are to do well. Check out Rob Toonen’s article on Goniopora in FAMA for a discussion of this process.

So, the bottom line - these photosynthetic organisms need light. And a lot. And they need food and a lot of that, too.

And they don’t need the light colored. They need a full spectrum, because they are better at using that than blue. You want to provide the best light for your corals - use bright day bulbs and probably at 5500 K (as this is pretty good daylight). The color drop off in the 2 or 3 feet of our tanks is measurable, but insignificant.

Any other color is less than optimal for the coral or the alga.

And, I am sorry, this isn’t an opinion. This is the way it is.

Now, as far as aesthetics. I have spent well over a thousand hours at depths of 60 feet or more. Organisms under blue light on a coral reef are ugly. Only a skosh away from being butt ugly. I can’t for the life of me understand someone who wants to make a nice pink "something” look black, but it would be that color using the blue light of 60 foot depths. But hey, you guys got your opinions on color. Well, aesthetics is where they belong. Not in a discussion of what the animals need.

[Dimorb]

Mycket läsvärt till och med.

Skulle vara bra om vissa handlar fick reda på detta så kanske de slipper att packa på en massa olika sorters ljus.

[Linnex]

Jopp men jag säger nog som Stig. Gult ljus (5500 K) är inte snyggt i karet.

[acuario]

Det är väl ingen nyhet att lägre kelvin är bättre för koraller men vill inte sätta i mina osram 5700k som jag hade för 10år sedan det var inte fint då och absolut inte nu men på den tiden så fanns det inget annat att välja på. jag tror på en blandning av olika kelvin spridd på olika ljuskällor annars så tror jag att 14000k är ett bra val och det kommer jag att fortsätta med i dagsläget