Moon lighting

MrClam

New member
I have DA moonlight kit for my tank with 2 led pods. Anyway after some time watching the cool lunar cycle function, I began to wonder if I was replicating the actual ocean conditions?

So, an odd question but does anyone know / have any diving experience around reefs to say how "bright" the reefs are under a full moon? I just want to make sure I am not blinding my fish while they try to sleep.
 
at one point I saw a par graph of Hawaii full moon.

A good amount of light still... but don't forget it's very diffuse, not intense at all...

And not all month long...

On that biological note, some corals are known to release eggs and sperm and stuff on a cycle of the moon... so that's a cool experiment if you can get it right!
 
Well I appreciate the advice joedc, but I am trying to replicate natural reef conditions and I dont think the moon turns off for a few hours at night. My question was in regards to the intensity of moon light at reef levels. The controller replicates lunar cycles, so some days are completely dark and then cycles to full moon ect. I will have to look for that par graph reefer. Thanks
 
Not the par graph, but a good place to start...

Different objects in the Solar System have a different amount of reflectivity. Astronomers call reflected light from the Sun albedo. The values for an object’s albedo can range between 0 (dark) and 1 (bright). The albedo for the Moon is 0.12. In other words, the Moon reflects 12% of the sunlight that falls onto it.

Read more: http://www.universetoday.com/19946/light-from-the-moon/#ixzz2Md5oqCqb

And lets see...

Wikipedia says the moon varies up to 1.0 'lux' which is "1 lumen per square meter". Some measurements...

10−4 lux Moonless, overcast night sky (starlight)[2]
0.002 lux Moonless clear night sky with airglow[2]
0.27–1.0 lux Full moon on a clear night[2][3][4]
50 lux Family living room lights (Australia, 1998)[6]
320–500 lux Office lighting[9][10][11]
10,000–25,000 lux Full daylight (not direct sun)[2]
32,000–130,000 lux Direct sunlight


http://en.wikipedia.org/wiki/Lux
 
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Photosynthesis on an ELP using PAR reflected from a natural satellite with the same size as our Moon, but at the Roche limit, could support a low rate of photosynthesis at full Moon.

http://online.liebertpub.com/doi/abs/10.1089/ast.2006.6.668

So we find that the small amount of light at the surface is enough AT FULL MOON to drive a low rate of 'terrestrial photosynthesis' which requires at least some light of 600-700nm range...

So, the full moon has enough intensity to support some photosynthesis...

Which means it offers a full spectrum at a very low intensity [in a monthly cycle].


Which kinda throws a wrench of us guys using only blue light to simulate moon cycles. Maybe I should throw 5 white LEDs in with my 132 LEDS blues for my moonlight!

lol it never ends!
 
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A cool article on corals detection of moonlight...

Here we report the presence of an ancient family of blue-light–sensing photoreceptors, cryptochromes, in the reef-building coral Acropora millepora... Our results demonstrate phylogenetically broad roles of these ancient circadian clock–related molecules in the animal kingdom.

http://stke.sciencemag.org/cgi/content/abstract/sci;318/5849/467

And in my current re-research into the subject, I stumbled upon the link I originally mentioned...

A goldmine of data for you.

moonpar.png


moonpar2.png


http://www.advancedaquarist.com/index_html/2012/7/lighting

Mix those graphs with how (600+nm) red drops @ depths, and you have your estimates!

photosyn8parvsdepth.jpg


:fish1: :beer: :fish1:
 
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Very nice graphs! But don't forget to account for the fact that when the moon (or sun) is low a lot of the light gets reflected by the surface and never reaches the animals in the water. So if one was to really replicate nature that would have to be part of the equation.
 
The last graph shows how certain nm drop off at depths [in full daylight] to help estimate.

In full daylight, corals at least 50 feet down are still getting some 600+ nm light.

Notice the spectrum of the moonlight has very little blue light actually within, ~33% Red, ~50% green+yellow light, leaving only ~17% blue light that the moon gives off...

But the moon gives off such little intensity, that I would doubt it would be enough to carry that red [600-700 nm] down even 10-20 feet in the water...

When accounting for this, the range of spectrum the moon-light provides to corals is still comfortably mostly in the Green-Yellow [500-600 nm] range. Anyway, it looks like to better duplicate the moon's light par, we should be offering more green/yellow light (with some blue as well) to the corals at a very very low intensity.

Not exactly duplicated by my blue-only LEDs... But they still look hella-cool at night!

And again we come to the old lighting debate - what the corals prefer vs what 'looks good' to our eyes.
 
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WOW That is some very nice data.

I think an appropriate lunar cycle will help our tanks for more then just photosynthesis.

Many animals use the moon for reproduction, travel, etc and our coral may use them in a completely different manner all together.

To the OP's question I would think light spectrum would be less important than mirroring the moons cycle (waxing/wanning) throughout the month.

Disclaimer: I am no scientist/biologist but nature uses the moon in an abundance of surprising ways so why not do our best to copy. ;)
 
The lunar cycle does play a critical role in reproduction in the wild reefs but I think it has a lot more to do with tides that rise and fall and carry larvae away.

As for what triggers it, I wouldn't know for sure but I'll still bet on the tides. It doesn't seem very logical to me to leave that up to moonlight. What if there's overcast or a storm? Does that mean they won't reproduce that month? I wouldn't think so.
 
Do tides follow a measurable change along with the moon cycle.

I know that the tides are caused by the moon but would there be a program we could write that could match up both the tides (pumps) and our moonlights to mirror both aspects?
 
I do not have moon lights. I have a mated pair of clown fish that lay and hatch eggs. So IMO moon lights are not needed. Tank life can tell moon cycles even if not directly connected via lightsource.
 
Reeferbat, thanks for the excellent information. Its not often that I ask a question and get data and not an opinion! Unfortunately I also have blue-based LED moonlights so will have to pick up some white lights to be closer to the natural spectrum.
 
WOW That is some very nice data.

I think an appropriate lunar cycle will help our tanks for more then just photosynthesis.

Many animals use the moon for reproduction, travel, etc and our coral may use them in a completely different manner all together.

To the OP's question I would think light spectrum would be less important than mirroring the moons cycle (waxing/wanning) throughout the month.

I concur... I doubt the corals gain much if any photosynthetic gains from the 1.0 Lux the moon puts out (Compared to the 100,000 Lux of full direct sunlight)

I think your on to something with the waxing/waning of the lights being more important than the spectrum... And as the one article sighted mentioned, some scientists believe that it is an ancient class of blue-detecting zoanth that allow the Corals to detect the Moonlight.

As for what triggers it [reproduction], I wouldn't know for sure but I'll still bet on the tides. It doesn't seem very logical to me to leave that up to moonlight. What if there's overcast or a storm? Does that mean they won't reproduce that month? I wouldn't think so.

I would also think the tides certainly play into it - but I would still suspect the moon's light as one of the triggers... it's monthly illumination as one trigger with tides being another possible.

The great thing about 'using' the moon, is even if there is a bad storm for days [blocking out light] the corals can still 'see' the about-full moon the days surrounding that event. And even then, that would be a local event not a world-wide coral event.

And I don't know, but I don't think reproduction is a sublimely timed event "Everyone at 12:14am exactly on only the Full Moon!" as much as a window or period of release more like 'Everyone within the same week surrounding Full Moon."

I have a mated pair of clown fish that lay and hatch eggs. So IMO moon lights are not needed.

True that. perfect replicated moon cycles and light are not needed to sustain life in our tanks.

I enjoy this topic as a theoretical "what if we could"? It could only help the corals as opposed to be a detriment I would think.

My expensive Vortech power-head with adjustable flow to mimic changing ocean conditions was not needed either [could have saved $200 and bought another Korelia]... but I still think it's a cool addition.

Reeferbat, thanks for the excellent information. Its not often that I ask a question and get data and not an opinion! Unfortunately I also have blue-based LED moonlights so will have to pick up some white lights to be closer to the natural spectrum.

Anytime man... I enjoy these discussions! They give me a reason to do more research. And like I said, I like the open discussion on the topic.

Anyway, I wouldn't add too much white lighting, as
A)it takes a lot of blue lighting to 'blue up' the tank look after adding white (like 2-3+ blue bulbs for each white or more depending on setup)
B) the real moonlight intensity would be sooo dim that even it will be very easy to 'overdo' the white light... Which might even have the detriment of inflicting photo-inhibition on the corals [too much light/no resting period can throw off the corals 'cycle' and make it under-productive in photosynthetic gains - almost like starving on too much light].
 
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