LED REEF LIGHTING. Advantages/Disadvantages Cost Analysis Lighting Facts Spectrum / Intensity Pigments / Colour Apples & Oranges Types of LEDs / Drivers.

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 (%)

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5000K - 10000K CCT

3700K - 5000K CCT

2600K - 3700K CCT

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Cree XT-E & XP-E

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Wavelength (nm)

White

Relative Radiant Power (%)

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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)

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Colored lines represent the percentage of sunlight penetration at the specified depth.

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Depth range of coral harvest

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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

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Abso

rptio

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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

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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

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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

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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%

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Ranges of greatest photosynthetic efficiency

7. Are high power (3W-5W) LEDs available for the range of wavelengths needed?

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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

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Fluorescent pigment excitation wavelength200 250 300 350 400 450 500 550 600 650 700

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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