Post on 01-Apr-2015
LED REEF LIGHTING
By
ReefLEDLights
www.ReefLEDLights.com
LED REEF LIGHTING• Advantages/Disadvantages• Cost Analysis• Lighting Facts• Spectrum / Intensity• Pigments / Colour• Apples & Oranges• Types of LEDs / Drivers• DIY • Pics and Questions
Advantage and Disadvantages
• Little Heat / No Heat• Low Energy Consumption• Long Life…11 Years• Great Coral Colours• Low Voltage• Able to Keep The Light Off The Glass
• Moderate Initial Investment • Changing Technology• Numerous Options• Tight Spread
MH Cost Analysis • 225 Gal SPS • 72”L x 30”H x 24”W• Maristar HQI 3 x 250 Watt MH
w 4 39W T5 Actinic Bulbs $825• 3 Lumatek Electronic Ballasts
$165 ea• Bulbs 4 9W T5 & 3 Ushio
250W DE $312 plus shipping• Total $2532• Annual Bulb Replacement $
312• Annual Electric Cost @ $0.12
KWH $374.25
LED Cost Analysis
• 225 Gal SPS • 72”L x 30”H x 24”W• 3 Quality Domestic
Fixtures @ $595 ea or $1785
• Annual Cost of 354W @ $0.12 KWH $129
• $1000 Less Expensive• Over $500 a year in
operating cost savings.
Cost Analysis
• The Results Simply Blow My Skirt UP
LED Reef Lighting Facts
• Most corals available to reef hobbyists are harvested between 2 and 20 meters.
• A coral’s spectral needs are determined by the depth range in which each coral naturally grows
• Coral can and do adapt to a change in light intensity• LED selection should reflect the lighting conditions in
which most corals grow• Coral growth rate is better when the amount of blue light
is increased
www.advancedaquarist.com/2008/12/aafeature1
ReefSpectrum vs Full Spectrum• Most Corals do not receive light in the Red or Green
Spectrum. These Wavelengths are severely limited below 10ft
• Coral growth rate decreases when the levels of red light are increased, even when accompanied by an increase in Kelvin rating
www.advancedaquarist.com/2008/12/aafeature1
• Red light can cause coral bleachingwww.advancedaquarist.com/2003/11/aafeature
• Corals have blue light-sensing photoreceptors that cue coral branching toward the blue light source, which is the dominant light in the coral environment. There is no corresponding red photoreceptor in corals.
http://jeb.biologists.org/content/212/5/662.full.pdf
250 DE HQI MH Bulbs
Spectrum For The CREE XT-E
• The Spectrum is perfectly suited for the reef aquarium.
• Compared to the 250 watt DE MH the Cree offers a wider wavelength without the UV.
• The UV is normally shielded by glass or in the case of SE MH bulbs the outer Bulb.
Relative Radiant Power (%)
100
80
60
40
5000K - 10000K CCT
3700K - 5000K CCT
2600K - 3700K CCT
20
0
Cree XT-E & XP-E
400 450 500 550 600 650 700 750
Wavelength (nm)
White
Relative Radiant Power (%)
100
80
6
0
4
0
2
0
0
Royal Blue Blue Green
400 450 500 550 600 650
Wavelength (nm)
Royal Blue
LED Binning
Ok, What Mix Do I Need
Factors In LED Choice
• LED Efficiency– More expensive 5 watt XT-E are ultimately
less expensive than 1, 2 & 3 watt LEDs • LED Colour Temp / Spectrum
– Personal Choice. Ginger v Mary Ann• LED Fixture Cost
– Numerous options and variables • Desired Intensity PAR
– 100-200 PAR on the Sandbed is Best.
Ocean depth at which the sun’s light is absorbed(Clearest coastal water category)
400 450 500 550 600 650 700Violet Blue Green Yellow Orange Red
4020
6080
100
120
Sun
light
wav
elen
gth
pene
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on d
epth
(met
ers)
90%
80%
50%
70%
60%
10%
20%
30%
40%
<1%
Colored lines represent the percentage of sunlight penetration at the specified depth.
10
Depth range of coral harvest
400 450 500 550 600 650 700Violet Blue Green Yellow Orange Red
Sunlight penetration to 1 meter and 10 meters depth50
%75
%25
%0%
10 meters 1 meter
Perc
ent o
f sun
light
pen
etra
tion
3. Which pigments do corals use in photosynthesis?
• Chlorophyll a:• The pigment that participates directly in the light-requiring
reactions of photosynthesis• Absorbs light very well at a wavelength of about 450 nm
(blue), and again with a higher peak at 675nm (red)
• Chlorophyll c2 • Is called “antenna” or “accessory” pigment, because it helps
to collect energy (photons) from light wavelengths which are not absorbed by chlorophyll a, then transfers the light excitation it absorbs to chlorophyll a.
• Chlorophyll c2 has absorption peaks at 450nm, but also at 581nm and 630nm
4. Additional Pigments That Aid In The Photosynthetic Process
• Carotenoids• Include Beta-carotene, peridinin and xanthrophylls
(diadinoxanthin and diatoxanthin)• Have two purposes:
• Beta-carotene, peridinin and xanthrophylls are also antenna pigments, because they help to collect light wavelengths which are not absorbed by chlorophyll itself. They pass their absorbed energy to chlorophyll.
• The perindin-chlorophyl a-protein (PCP) is a light-harvesting complex that uses perindin as its main light-harvester.
• Xanthrophylls also absorb excessive energy that chlorophyll cannot use, dissipating that unused energy so that the photosynthetic apparatus is not damaged.
5. Wavelengths That Are Absorbed By Each Pigment In The Photosynthetic Process
400 450 500 550 600 650 700Violet Blue Green Yellow Orange Red
Abso
rptio
n
Chlorophyll a
Chlorophyll c2
PCP complex
Note: These pigments all have peaks between 400 and 500nm, matching the penetration of the blue wavelengths. Are the peaks above 600nm only applicable to shallow water corals?
5. Wavelengths That Are Absorbed By Each Pigment In The Photosynthetic Process
400 450 500 550 600 650 700Violet Blue Green Yellow Orange Red
Abso
rptio
n Diatoxanthin
Diadinoxanthin
Β-carotene
Note that these pigments all have peaks between 400 and 500nm, matching the penetration of the blue wavelengths
6. Different Rates Of Photosynthesis At Each Wavelength
400 450 500 550 600 650 700Violet Blue Green Yellow Orange Red
Photosynthesis as a function of absorbed wavelength
Photosynthetic efficiency is best between 400-500nm, and between 630-680nm.Note that the rate of photosynthesis drops off dramatically above 500 nanometers.
Efficiency midpoint
Greatest photosynthetic efficiency
Greatest photosynthetic efficiency
The arrows represent the top 50% of the light absorption capability of each pigment
400 450 500 550 600 650 700Violet Blue Green Yellow Orange Red
PCP
β-carotene
Chlorophyll c2
Chlorophyll a
Diatoxanthin
Diadinoxanthin
Chlorophyll a
Note how the most efficient rate of light absorption by pigments coincides with the best rate of photosynthetic activity
Ranges of greatest photosynthetic efficiency
Photosynthetic efficiency vs. wavelength penetration
400 450 500 550 600 650 700Violet Blue Green Yellow Orange Red
4020
6080
100
120
This is another way of looking at the data. Note how the rate of photosynthesis drops off significantly at 500nm, coinciding
with the steep decline of the rate of light penetration above 500nm.
90%
80%
50%
70%
60%
10%
20%
30%
40%
<1%
Sun
light
wav
elen
gth
pene
trati
on d
epth
(met
ers)
Ranges of greatest photosynthetic efficiency
7. Are high power (3W-5W) LEDs available for the range of wavelengths needed?
400 450 500 550 600 650 700Violet Blue Green Yellow Orange Red
4020
6080
100
120
Sun
light
wav
elen
gth
pene
trati
on d
epth
(met
ers)
Philips or Luxeon Cyan 505
Semi P2N-U LED Violet/UV 410-420
430nm (generic Chinese)
Cree XP-E Blue 470
Luxeon Royal Blue 450
Cree XT-E Royal Blue 450-465nm
8. Lighting Intensity Needs of Corals
• Coral lighting is measured in units of photosynthetically active radiation (PAR)
• PAR is a measurement of µmol photons/m2/second
• It’s been a generally accepted rule that corals typically need a minimum PAR of 100, while some corals need much higher values.
• Actual experiments show that the rate of photosynthesis reaches its maximum at a point called “photosaturation”
• Typical photosaturation points range between PAR values of 100-400
• The point above photosaturation where too much light is present, a situation potentially harmful to the coral/symbiont, is called “photoinhibition”
• Photoinhibition is seen as a decrease in the rate of photosynthesis, even as light intensity increases
• Photoinhibition may occur at very low PAR values (250 and lower)• This means that in all but rare cases, more light is NOT necessarily better
Lighting Needs of Corals
• Shorter wavelengths• have higher energy• penetrate much deeper• produce a higher photosynthetic response than other wavelengths
• PAR meters measure the photosynthetic photon flux (area) density
• They do not account for the photosynthetic response in each region of the visible spectrum (e.g., blue light produces 3 times the photosynthetic response as green)
• If most of the light supplied is in the blue region of the spectrum, it is a reasonable assumption to conclude that one would need fewer LEDs, possibly by half or more, than if white were used LEDs alone
• This part is Art and no single recipe will be lauded by all
• Process• Add a few UV / Violet, Reds or Greens• Use dimmable drivers to tweak the colour perfectly• Avoid too much as in any recipe too much spice will ruin the dish
Highlighting Pigments in Corals
Fluorescent Pigments• The following graph to compares excitation wavelengths (wavelengths of
light absorbed by fluorescent pigments) with the emitted fluorescent light for the 90 different pigments listed in an Advanced Aquarist article. (www.advancedaquarist.com/2006/9/aafeature)
• The data on the graph is limited to the data provided in the article• The vertical axis is the wavelength of light emitted by the excited molecules in
the pigments• The dots are colored to match the color of the emitted light
• The horizontal axis is the light wavelength that the pigment absorbs• Line “A” represents the boundary between UV and visible light• Line “B” represents the point at which the rate of photosynthesis drops off,
around 500 nanometers (nm)• “Wavelength” is the distance between successive peaks of a wave• A nanometer is 1 billionth of a meter, or one millionth of a millimeter
• Line “C” represents the longest peak wavelength at which fluorescent pigments are stimulated (583nm)
• When a pigment has multiple excitation and/or emission peaks, I’ve graphed each excitation/emission pair separately, which is why there are 169 points on the graph compared to 90 pigments listed in the article
• For example, if one pigment is excited by 450nm, and emits light at 500 and 550nm, you’ll see a point on the graph at (450,500) and (450,550)
Fluorescent Pigments• Interesting reading in the article found here:
• http://www-personal.usyd.edu.au/~cox/pdfs/nat_preprint.pdf• The fluorescent emissions from some pigments may actually serve to excite
other pigments to fluoresce• An experiment was conducted in which one pigment produced weak green
emissions between 330 and 380nm when excited by 482nm (blue) light• A blue-emitting pigment was then mixed in solution with the green-emitting pigment
(blue pigment’s excitation peak was at 382nm)• When the two pigments were exposed to 382nm light, the green emission
increased by 4 to 7 times
• Fluorescent pigments are believed to have multiple purposes:• In excessive sunlight, they dissipate excess energy from light wavelengths that
don’t contribute significantly to photosynthesis• Reflect ultraviolet and infrared light• Regulate the light environment of coral host tissue, actually collecting additional
light energy in low-light environments
Pigm
ent e
mis
sion
s in
the
vis
ible
spe
ctru
m
Fluorescent pigment excitation wavelength200 250 300 350 400 450 500 550 600 650 700
400
450
500
550
600
650
700
Violet
Blue
Green
Yellow
Orange
RedA B C
Fluorescent Pigments
Violet Blue Green Yellow Orange Red
RGB
• Red Green & Blue have been used in combination to produce almost any colour.
• The first colour TVs colour film and even modern flat screen displays use RGB to produce almost any colour
Why Use RGB ?• Red Green & Blue can produce almost any colour.• Why add tertiary non growth LEDs like Lime or Yellow when with the proper
control you can tweak the looks of your reef and even offer a different look based on the time of day.
• Your Primary Grow is 420-480nm. Based upon the previous pigment chart you have the flexibility to highlight these pigments efficiently to suit your individual taste.
• After you have the grow solved you want your reef to look the best without adding too much of the warmer spectrum which may enhance nuisance algea.
Conclusions?
• Most fluorescent pigments (111 of 169) are excited by peak wavelengths between 400 and 510nm
• 76 pigments are excited by peak wavelengths between 400 and 499nm
• 35 pigments are excited by peak wavelengths between 500 and 510nm
• Red light does not excite the fluorescent pigments, infact it’s the first wavelength blocked by the ocean
• Max excitation peak wavelength is 576nm (orange)• Only 7 of the pigments are excited by UV light
OK How Many Watts Do I Need
Never Compare Fixtures By Watts
• Many are shocked to learn that Fixture Wattage is a poor judge of LED light output (PAR) and penetration
Comparison Of Three Similar Wattage Fixtures
EBAY Chinese Fixture
145 watts 200PAROK Chinese Fixture
139 Watts 397PAR
Domestic Fixture150 Watts 700 PAR
DIFFERENT TYPES OF LEDSEpistar 3 wattUp To 700mA180 Lumins @ 700mA or .25 l/mACREE XP-EUp To 1000mA122 Lumins @ 350mA or .34 l/mACREE XT-EUp To 1500mA139-160 Lumins @ 350mA or .39 l/mA428 Lumins @ 1500mA or .28 l/mALuxion ESUp To 1000mA351 Lumins @ 1000mA or .35 l/mA
Drivers
• Standard
• Dimmable – PWM – Analog
Forward Voltage and Current
Mean Well LPC 35-700Forward Voltage of 9-48
Constant Current of 700mA
Mean Well ELN 60-48DForward Voltage of 24-48
Constant Current of up 1.7A
CREE XR-E
Forward Voltage of 3.2-3.6
LPC 35-700
9/3.2= 2.81 48/3.6=13.33
ELN 60-48D
24/3.2= 7.5 48/3.6=13.33
DIY How To
Solderless DIY
• Much Easier• LEDs Can Be
Swapped Out or Changed
• No Soldering Mistakes
• Use BJB Solderless Connectors
Solderless Build
Solderless Build
Solderless Build
• Build Questions?
Know The Facts and OptionsDon’t Be This Guy
Questions
• Sources– www.advancedaquarist.com/2008/12/aafeature1– www.advancedaquarist.com/2008/12/aafeature1– www.advancedaquarist.com/2003/11/aafeature– http://jeb.biologists.org/content/212/5/662.full.pdf
• Special Thanks– Dana Riddle– Dan Kelley aka Crit21 on RC