Can anyone explain what light spectrum/temp means?

[Cbray305]

Thanks in advance. I have some fluval seas on my 55.. they do not produce the best PAR. However , would like to get the most i can put of the light.

So can anyone explain how to breakdown or understand the spectrum/temp meanings so i can understand how to make the most out of the spectrums so the lights i have can work to their full potential? They say 25 000 k on the box.

 

[Ron Reefman]

Spectrum is a wavelength measurement and each one is a slightly different color. 400nm are blue and they run through 500nm green, 600nm yellow, 650nm orange and 700nm red.

Color temp is much more technical. It's used for white light (a mix of all or almost all color spectrum). Basically, red, blue and green make up white light. Low color temps like 6500K, are white light that is tinted or leaning toward red. High color temps like 16,000K are white light that is tinted blue. The red and blue ends of the chart below are slightly exaggerated colors, they are really more white than red or blue.

To get the most out of your particular fixture, which as you are already aware, puts out low PAR levels, you want to run the blue and violet leds as high as you can. The blue spectrum light is what the zooxanthellae (algae) inside your corals use for photosynthesis which helps feed the coral. There is some blue spectrum in the white light, so it helps, but not nearly as much. The problem with the white light is, there is also red spectrum in it and that is what nuisance algae uses for photosynthesis.

 

[billybwf]

Nice explanation as said blue should be dominating others are mixed in to a level that is better looking for you not necessarily the corals

 

[VAFish]

Spectrum is a wavelength measurement and each one is a slightly different color. 400nm are blue and they run through 500nm green, 600nm yellow, 650nm orange and 700nm red.

Color temp is much more technical. It's used for white light (a mix of all or almost all color spectrum). Basically, red, blue and green make up white light. Low color temps like 6500K, are white light that is tinted or leaning toward red. High color temps like 16,000K are white light that is tinted blue. The red and blue ends of the chart below are slightly exaggerated colors, they are really more white than red or blue.

To get the most out of your particular fixture, which as you are already aware, puts out low PAR levels, you want to run the blue and violet leds as high as you can. The blue spectrum light is what the zooxanthellae (algae) inside your corals use for photosynthesis which helps feed the coral. There is some blue spectrum in the white light, so it helps, but not nearly as much. The problem with the white light is, there is also red spectrum in it and that is what nuisance algae uses for photosynthesis.

Very impressive explanation.

 

[Ron Reefman]

Just an extra point, some of the green, yellow, orange and red spectrum do help with color, pigment production and a few other coral chemistries, but all in all, they are less important than food!

I worked for an aquarium led fixture company for a couple of years after I retired my regular job. ;Wideyed;Woot;Woot

 

[Cbray305]

Thank you. I have had some algea issues, so i reduced my whites to 5%... however, could be a coincidence, my condy anenemone since has climbed literaly to the very top of tank. So.i have raised my whites back to 35... which are really bright. Was wondering if the lack of white caused a loss of PAR for the anemone or coral

 

[FishTruck]

I copied this from a shutterbug post... but here is why we use the term "temperature", and why warm colors are actually cold colors and cold colors are actually warm.

It's about how things glow when heated up.

Consider: You can look at a set of billiard balls, and while they all have different colors, those tints have nothing to do with their temperatures (which are, needless to note, all the same). But grab the eight ball, which is black—no color—and put it in a laboratory oven. Ramp up the heat. It will remain black until the temperature reaches about 900 degrees F, at which point it begins to glow a menacing dull red. That temperature equates to about 740 degrees K (or Kelvin). The Kelvin scale is considerably more convenient for scientists, because the coldest temperature that anything can be (which is -460 degrees F) is defined as being 0 K. No negative temperatures.

At 1,000 K, or 1,340 F, the eight ball glows salmon pink, and could serve as a flattering key light for photography. At 3,000 K, it’s the hot yellow color of an incandescent bulb, and at 6,000 K imitates the outer layers of the Sun—a daylight light source. Heat it to 30,000 K, and you’ll need to set your white balance to “ultraviolet,” as well as slather on some sunblock.

The color of hot light sources clearly depends on temperature—the hotter, the bluer. This may confuse the innocent, because photographers usually refer to candles and incandescent bulbs as “warm” light sources, whereas shady outdoor areas, mostly lit by blue sky, are considered “cool.” But in terms of temperature, it’s just the opposite: light bulbs are far cooler than the surface of the Sun.

 

[Ron Reefman]

Thank you. I have had some algea issues, so i reduced my whites to 5%... however, could be a coincidence, my condy anenemone since has climbed literaly to the very top of tank. So.i have raised my whites back to 35... which are really bright. Was wondering if the lack of white caused a loss of PAR for the anemone or coral

Loss of white intensity does reduce the PAR. PAR is the level of all spectrum that various plants can use for photosynthesis. So lowering the intensity does lower the PAR.

To confuse things even more, there is PUR (Photosynthetic Usable Radiation). This is VERY difficult to measure because every plant and algae use a variety of different spectrum to do photosynthesis. So even if you could know the PUR for a particular coral, and set a meter to measure just that. It would be less useful for any other coral because it would use spectrum that are slightly different. So as far as most reefers are concerned, PUR is blue spectrum from 400nm to 500nm.

So as far as your Condy anemone is concerned, dimming the white light is much less of an issue than dimming the blue light. But there is still some effect.

 

[jda]

Any competent reef light will grow algae if your tank conditions are conducive for it. Limiting just one part of the spectrum is an ages-old myth that does not get you very far - tanks with heavy blues are covered in hair algae just like tanks with more white.

I strongly recommend to watch this. It is an hour that can really help your reefing career for ever. Tullio presented this at MACNA a few years ago and he owns ReefBrite and knows his lights. This will help you avoid some of the common mental errors and misconceptions that a lot of people have about light. The Facts of Light: