Need help with led lighting

[bgilson]

My wife has decided to get some corals for the tank. We have a light already but neither of us understand the lighting and how to get it where it needs to be for the corals. The corals need par 120-250. Also the coral site mentioned a 14-20k spectrum. This is all greek. I have added a pic from the light I have. Can sometime put all this in english for me please.

 

[ZoWhat]

Sunlight is made up of the entire spectrum you see charted, from ultraviolet purple to blue to green to yellow to red light.

Interesting fact is all white light even on your monitor or phone is the entire spectrum of blues thru the red light wavelengths coming at your eyes mixed all together, at the same moment....

As sunlight penetrates thru every foot of ocean water the Reds (first) and yellows (second) get filtered out. The deeper you go the only thing left is blues and purples (ultraviolet)

In the wild most corals live in 5 to 30ft of water. At 30ft its mostly blue light that is left.

NOTE: All we are doing with reef lights is to SIMULATE sunlight at roughly 15ft of ocean water producing blue light more pronounced over green, yellows and reds

It's good your light is charted to have plenty of blue

PAR is the intensity of the light. Meaning how strong.

Depending on your coral, which you say you need 150 PAR, that's a mid range for PAR. not too strong, not too weak.

So in the end your light is simulating sunlight at roughly 15ft deep in the wild where green yellow and reds are filtered out


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[bgilson]

Sunlight is made up of the entire spectrum you see charted, from purple to blue to green to yellow to red.

As sunlight penetrates thru every foot of ocean water the Yellow s and reds get filtered out. The deeper you go the only thing left is blues and purples.

In the wild most corals live in 5 to 30ft of water. At 30ft its mostly blue light that us left.

It's good your light is charted to have plenty of blue

PAR is the intensity of the light. Meaning how strong.

Depending on your coral is you need 150 PAR, that's a mid range for PAR. not too during, not too weak.

So in the end your light is simulating sunlight at roughly 15ft deep I the kcrwn where green yellow and reds are filtered out


.

So is the light I currently have able to do 150 par? It says 85 at 12” but obviously thats not enough. So im assuming higher correct?

 

[ZoWhat]

Is it a 20w light I'm reading? At 20watts not much PAR is being reproduced.

Many times a LFS will have a PAR meter you can rent for the day to get a reading in your own tank

One end of the cable is an Optical eye, the other end a handheld device that with digitally tell you the PAR

 

[FurrierTransform]

I'll start and maybe others can finish: The color temperature is a measure of the peak wavelength of your light spectrum (obligatory physics explanation: The color temperature concept comes from the black body formulation of radiation and assumes a particular spectrum. From Wien's Law, one may deduce the peak wavelength for a particular color temperature, but note that this does not necessarily imply your light source behaves as a black body.) Color temperature takes your light spectrum and estimates a black body temperature which looks like your light. Since your light is heavily blue, you probably have a 20,000 K temperature.

Your proposed light has a blend of a number of LEDs and I bet they have a nice looking spectrum for corals and viewing. The photosynthetic requirements of corals and anemones are in the 450 nm range (terrestrial plants do best with both blue and red, but red doesn't penetrate water as well as blue). Why doesn't one use just blue light? because it doesn't look as nice as blue plus white light. You'll see on this site lots of photos taken under only blue light. Not as nice looking, right?

PAR is a measure of intensity (I think) meaning photosynthetically active radiation. Your light has a PAR of 85 at 12" of air. PAR measured through water will be less, but I do not know how much less. If you want higher PAR, it looks like you'd need to get another light or place your coral pretty close to the surface. How deep is your tank? You may have also noticed on this site that frag tanks are typically very shallow, for this very reason.

I hope this helps, if not, ask away! Maybe you'll stump me but someone else will be sure to know

 

[ZoWhat]

Usually a 6ft cable