Category Archives: Aquarium Lighting

TMC AquaRay NUV 410nm LED

AquaRay Logo
Revised 1/7/16

1380542_595504497173285_1626878484_nTMC AquaRay has finally granted the AquaBeam NUV 410nm LED to be released to the US market. The LED was released to Europe back in 2013 and only to the UK, for quantity control issues. The LED has the same design as the rest of the Solid State AquaRay line, with 5 SemiLED x 410nm near-ultra violet (NUV) didoes, 120 beam angle. It has the waterproof rating of IP67, no fan, shimmer, low carbon output/watts, PWM dimming, and the 5 year full replacement warranty.

20160106_122637

At this point of 2016, American Aquarium Products is the only supplier of these LED to the Western hobbyist. The point of a emitter in this range is to enhance the colors of corals, fish, and plants.

TMC States:

This 410nm wavelength will make corals fluoresce (as well as some other critters and fish) and has been shown to improve the red pigment ratio of certain deep water coral species such as Lobophyllia and Trachyphyllia.

“The addition of this wavelength makes LED lighting look even closer to natural sunlight, truly the true to nature lighting solution you can buy!”

Resource: AAP AquaRay NUV LED

AquaRayNUV

Since this lighting spectrum is in the far side of the lighting spectrum, which also dips into the UVB range, limited quantity/amounts of the light is suggested.

TMC rates on strip of 5 emitters to light up to 170gals/650 litres, and is best seen when the tank is extra dark, say at night, when daytime lighting is off. The LEDs can be used during day lighting hours, just the recommendations of one strip per 170gals has to be considered for true coloration and amounts of UVB provided.

There are other Ultra Violet LEDs out in other commercial fixtures to date, but nothing up to TMC standards of quality of build, and also as a stand alone fixture. Some marine fixtures do have a couple NUV emitters in their fixtures, but separate controllability is not an option, which is why a separate fixture is preferred.

TMC does not give a rating on how long to run the fixture, say all the way threw the night, so caution is advised for health in mind. Start slow and work your way up and also know, limit amounts of this lighting type (more to the UVB range) actually reach the Earth surface.

AquaRayNUV2013

TMC NUV with Reef White Combo

Watch your eyes, as it can be quick to try and blind you. UVB is harmful, so consider safety.

The fixture could be considered for reptile use, but keep in mind, it has a purple/blue look and since this is a new technology, reptiles would really need to be watched as far as health, as no reptile UVB LEDs are on the market as of yet.

repitlesunUVB

Standard UVB Fluorescent

NUVSpectrum

NUV Spectrum

Considering the amount of energy used by both fixtures, the NUV could be used as a supplement UVB light, to be ran all day during normal daylight hours for reptiles. For reef tanks, volume of water needs to be considered. The supplement light can be ran all day on 170 gals of water.

Guest Authored By: Devon Trigg

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Helpful Aquarium & Pond Keeping Acronyms, Abbreviations

While not a complete list, these are acronyms I have found useful and many of my professional aquarium keeping friends have “thrown around”

  • A:

    AAP- An online aquarium & pond supply company, well known for their vast experience and research based information library.
    AMP – Ampere; is the SI unit of electric current. Reference: Ampere; Wikipedia
    AA – Amino Acid
    AC – Activated Carbon, a chemical filtration media.
    AC – Alternating Current
    Acan – Acanthastrea, a genus of large stony coral.
    Acro – Acropora, a genus of small stony coral. Reference: Acropora Coral Information and Care; Lighting, Amino Acids, more
    AEFW – Acropora (Acro) Eating Flat Worms
    ALK – Alkalinity, the measure of the alkaline buffering capacity of water. Reference: Aquarium Chemistry Complete
    ATC – Automatic Temperature Control

  • B:

    BA – Bubble Algae
    BB – Beneficial Bacteria
    BBA – Black Beard Algae. Reference: Aquarium Algae Control
    BBS – Baby Brine Shrimp
    BGA – Blue-Green Algae. Reference: Blue Grean Algae; Cyanobacteria
    BN – Bristle Nose Pleco, Ancistrus sp, a genus of plecos.
    BOD – Biological Oxygen Demand
    BPS – Bubbles Per Second, used as a measure of the CO2 rate entering an aquarium by advanced planted aquarium keepers.
    BTA – Bubble Tip Anemone
    BTU – British Thermal Unit

  • C:

    Ca – Calcium, an alkaline earth metal. Reference: Aquarium Chemistry Complete
    Ca(OH)2 – Calcium Hydroxide, used to make Kalkwasser. Reference: Aquarium Chemistry Complete
    CaCl2 – Calcium Chloride
    CaCO3 – Calcium Carbonate. Reference: Aquarium Chemistry Complete
    CAE – Chinese Algae Eater
    CBB – Copper Banded Butterfly
    CBS – Coral Banded Shrimp
    CC – Cubic Centimeter
    CC – Crushed Coral, sized #2 through #5. Reference: Aquarium Substrate
    CFL – Compact Fluorescent Lamp
    CFM – Cubic Feet per Minute
    Cl – Chlorine
    CL – Closed Loop
    CMS – Cubic Meters per Second
    CO2 – Carbon Dioxide, a colorless gas of one carbon and two oxygen atoms.
    CO3 – Carbonate
    CRS – Crystal Red Shrimp, Caridina cantonensis
    Cu – Copper, a reddish metallic element.
    CUC – Clean Up Crew, critters that remove algae and detritus.
    CWC – Continuous Water Change. Reference: Aquarium Cleaning
    Cyano – Cyanobacteria, commonly referred to as slime algae. Reference: Blue Grean Algae; Cyanobacteria

  • D:

    DC – Direct Current
    DD – DownDraft, a type of protein skimmer.
    DI – De-ionized water, also known as distilled water depending upon method used to achieve the same results which is completely mieral and ion free water. Reference: Do Fish Drink? Use of RO/DI, Soft Water for Aquarium; Osmoregulation in Fish

  • E:

    None at this time

  • F:

    FAQ – Frequently Asked Questions, acronym of speech
    Fe – Iron
    FO – Fish Only, a type of marine aquarium
    FOWLR – Fish Only With Live Rock, reef aquaria with no corals but with “live rock”
    Frag – Fragment of coral, usually acropora, that grows into a new piece of coral
    Fragging – Similar to above, this is the act of growing new corals using pieces of other corals
    Fuge – Refugium
    FW – Fresh Water

  • G:

    GAL – Gallon
    GBR – German Blue Rams, Mikrogeophagus ramirezi
    GBR – Great Barrier Reef
    GBTA – Green Bubble Tip Anemone
    GFCI – Ground Fault Circuit Interrupter, an AC plug designed to prevent electrical shock.
    GFI – Ground Fault Interrupter
    GFO – Granular Ferric Oxide, a chemical filtration media generally used for phosphate & silicate removal. Reference: Aquarium/Pond Filter Media

  • GH – General Hardness, a measure of calcium and magnesium. Reference: Aquarium Chemistry Complete
    GHA – Green Hair Algae. Reference: Aquarium Algae Control
    GPD – Gallons Per Day, a measurement of flow.
    GPH – Gallons Per Hour, a measurement of flow.
    GPM – Gallons Per Minute, a measurement of flow.
    GSA – Green Spot Algae. Reference: Aquarium Algae Control
    GSP – Green Star Polyps

  • H:

    H2S – Hydrogen Sulfide
    HCO3 – Hydrogen Carbonate
    HID – High Intensity Discharge lighting, metal halide and mercury vapor. Reference: Aquarium Lighting; Complete
    HITH – Hole in the Head, a fish ailment, common with cichlids. Reference: Hole in the Head, HITH Disease in Fish
    HLLE – Head and Line Lateral Erosion, a fish ailment, more common in marine species. Reference: What is a lateral line in fish? The functions and diseases of the lateral line
    HO – High Output fluorescent light
    HOB – Hang On Back filter, also a term for a type of skimmer. Reference: Aquarium Filtration
    HQI – Mercury (Hg) Quartz Iodide, a type of metal halide lamp. Reference: Aquarium Lighting; Complete

  • I:

    I – Iodide
    IO3 – Iodate
    IR – Infrared, a type of light with a longer wave length than visible light. Reference: Aquarium Lighting; Complete

  • J:

    None at this time

  • K:

    K – Kelvin rating, color temperature of the light source. Reference: Aquarium Lighting; Complete
    K – Potassium
    KALK or KW- Kalkwasser, German for calcium hydroxide solution or limewater. Reference: Aquarium Chemistry Complete
    kg/L – kilograms per liter
    KH – Carbonate Hardness, a measure of carbonates. Reference: Aquarium Chemistry Complete
    KI – Potassium Iodide
    KMnO4 – Chemical formula for potassium permanganate. Reference: Aquarium Medications Part 3; Potassium Permanganate
    kWh – KiloWatt-Hour

  • L:

    L – Liters
    LED – Light Emitting Diodes. Reference: Aquarium Lighting; Complete
    LFS – Local Fish Store (or Shop)
    lm – Lumen, the unit for amount of light from a light source. Reference: Aquarium Lighting; Complete
    LPD – Liter Per Day, a measurement of flow (metric).
    LPH – Litre Per Hour, a measurement of flow (metric).
    LPM – Liters Per Minute, a measurement of flow (metric).
    LPS – Large Polyped Scleractinian, a stony coral, has large and soft polyps. Reference: Acropora Coral Information and Care; Lighting, Amino Acids, more
    LPS – Local Pet Store
    LR – Live Rock, rock with living organisms including nitrifying and de-nitrifying bacteria within it. Reference: Marine Aquarium Care Basics
    LS – Live Sand, sand with living organisms including nitrifying and de-nitrifying bacteria within it.
    LTA – Long Tentacle Anemone
    Lx or Lux – the amount of light per square meter (lm/m2). Reference: Aquarium Lighting; Complete

  • M:

    Ma- MiliAmps
    MACNA – Marine Aquaria Conference of North America, held annually
    MASNA – Marine Aquarium Societies of North America
    MCF – Midwest Coral Farms, a well known coral farm in the Chicago area.
    MEQ/L – Milli-Equivalents per Liter, a measure of alkalinity.
    Mg – Magnesium, a trace mineral. Reference: Aquarium Chemistry Complete
    mg/L – Milligrams Per Liter, 1 mg/L = 1 ppm (parts per million).
    MH – Metal Halide light. Reference: Aquarium Lighting; Complete
    MTS – Multiple Tank Syndrome
    Mv – MilliVolts
    MW – Microworms

  • N:

    N – Nitrogen
    Na – Sodium
    NaCO3 – Sodium Carbonate
    NaOH – Sodium Hydroxide
    NH3 – Ammonia, a compound of nitrogen and hydrogen. Reference: Aquarium/Pond Nitrogen Cycle
    NH4 – Ammonium, a compound of nitrogen and hydrogen.
    nm – NanoMeter, commonly used as a unit for wavelength(color) of light. Reference: Aquarium Lighting; Complete
    NO2 – Nitrite, a product of ammonia oxidation.
    NO3 – Nitrate, a result of nitrites converted by Nitrobacter bacteria. Reference: Aquarium/Pond Nitrogen Cycle
    NTS – New Tank Syndrome

  • O:

    O2 – Oxygen, a colorless, tasteless, odorless gaseous element OEBT – Orange Eye Blue/Black Tiger shrimp
    ORP – Oxidation Reduction Potential, more correctly now known as Redox balance which is the blance of both Oxidation AND Reduction, both proven to be essential for life, including aquatic. Reference: Aquarium Redox

  • P:

    P – Phosphorus
    PAS – photosynthetic action spectrum, another term for PUR. Reference: Aquarium Lighting; Complete & PUR vs PAR in Aquarium Reef/Planted Lighting; LED Wavelengths
    P04 – Phosphate
    PAMR – Professional Aquarium Maintenance & Research. An abbreviation or credential applied to persons with years of experience in professional aquarium/pond keeping and research, as opposed to the many posers lurking in Facebook groups and Yahoo Answers.
    PAR – Photosynthetically Active Radiation. Reference: Aquarium Lighting; Complete & PUR vs PAR in Aquarium Reef/Planted Lighting; LED Wavelengths
    PC Power Compact fluorescent light
    pH – Potential Hydrogen, a measure of the acidity or alkalinity of a solution. Reference: Aquarium Chemistry Complete
    PNWMAS – Pacific Northwest Aquarium Society
    PO4 – Phosphate
    pods – A popular term for Copepods
    PP – Potassium Permanganate, a chemical used in fish baths & swab as well as used to kill snails, snail eggs, and some parasites. Reference: Aquarium Medications Part 3; Potassium Permanganate
    PPM – Parts Per Million, 1 ppm = 1 mg/L
    PPT – Parts Per Thousand
    PSI – Pounds per Square Inch
    PVC – Poly Vinyl Chloride, used for piping and plumbing.
    PWC – Partial Water Change
    PUR – Photosynthetically Usable Radiation, another term for photosynthetic action spectrum. Reference: Aquarium Lighting; Complete & PUR vs PAR in Aquarium Reef/Planted Lighting; LED Wavelengths

  • Q:

    QT – Quarantine Tank. Reference: Aquarium Disease Prevention
    QT – Quart of liquid
    QM – Quality Marine USA, generally regarded as the premier seller of wholesale marine livestock, and now freshwater too.

  • R:

    RCS – Red Cherry Shrimp, Neocardinia heteropoda var. ‘red’
    RDSB – Remote Deep Sand Bed
    RO – Reverse Osmosis, a type of water purification that removes most contaminants & minerals, but leaves some ions. Reference: Do Fish Drink? Use of RO, Soft Water for Aquarium; Osmoregulation in Fish
    RO/DI – Reverse Osmosis, followed by De-Ionization, a type of water purification to removal all minerals and mineral ions. The result is 100% neutral water with a pH of 7
    RMA – Return Merchandise Authorization. Many larger aquarium/pond supply retailers requires these be filed before returning defective, damaged, or simply unwanted merchandise. This is often a way to lower return numbers in the same way companies know that many rebate offers are not returned. I suggest to look for online businesses that do NOT require RMAs!
    RTN – Rapid Tissue Necrosis, protozoal infection of corals; can be rapidly fatal if not treated.
    RUGF – Reverse flow UnderGravel Filter

  • S:

    SAE – Siamese Algae Eater, Crossocheilus oblongus
    SAL – Salinity
    SG – Specific Gravity, a measurement of saltwater density, generally the most simple measurement of the amount of salt in a marine aquarium, although not as accurate as an Aquarium Refractometer.
    Si – Silicon
    SPS – Small Polyped Scleractinian, stony corals with very small polyps. Reference: Acropora Coral Information and Care; Lighting, Amino Acids, more
    Sr – Strontium, an alkaline earth metal.
    STN – Sudden Tissue Necrosis, protozoal infection of corals; can be rapidly fatal if not treated.
    SW – Salt Water or Sea Water

  • T:

    T5HO – T5 High Output light bulbs. Reference: Aquarium Lighting; Complete
    TDS – Total Dissolved Solids, the portion of solids in water that can pass through a 2 micron filter. Reference: Do Fish Drink? Use of RO, Soft Water for Aquarium; Osmoregulation in Fish
    TFC – Thin Film Composite, a type of RO membrane.

  • U:

    UGF – Under Gravel Filter, a method of aquarium filtration
    UV – Ultra Violet, a spectrum of light. Commonly the UVC Spectrum is used for aquarium or pond sterilization and clarification as well as improved Redox balance by better UV Sterilizers generally found at higher end retailers. Reference: Aquarium/Pond UV Sterilization
    UVC – The effective sterilization spectrum of UV light energy

  • V:

    V – Volt
    VHO -Very High Output, a type of fluorescent light. Reference: Aquarium Lighting; Complete

  • W:

    W – Watts, a unit of power
    W/D or WD- Wet-dry, a method of aquarium filtration that is excellent at ammonia/nitrite removal, but also often results in high nitrates. Often used in the wrong aquarium applications and is often incorrectly recommended, especially for planted aquariums. Reference: Aquarium Filtration
    W/gal – Watts per Gallon
    WC – Water Change
    WC/PWC – Water Change/Partial Water Change
    WCMM – White Cloud Mountain Minnow
    WPG – Watts Per Gallon, a generally outdated method of measuring light requirements, however it is still useful when comparing apples to apples. Reference: Aquarium Lighting; Complete

  • X:

    None at this time

  • Y:

    None at this time

  • Z:

    ZC – Zoanthid Coral, a family of corals. Reference: Zoanthid Reef Aquarium Care & Lighting

A similar but LESS accurate list can be found here:
About Home; Aquarium Acronyms
It misses VERY important terms such as PUR and PAS while missing important leaders of the aquarium hobby/industry too

What to Consider When Choosing Your Aquarium LED Lights

See the In-Depth LED Comparison Chart at the end of this article.
After clicking on it to enlarge, it can be saved to as a picture file for future reference too!

Please also read my more in depth LED article (which has more pictures too):
LED Aquarium Lights, Lighting; How they work
As well please read the many references throughout this article.

spectrum
There are two main reason to have proper lighting over your aquarium. The first is to be able to see our inhabitants and the other reason is to support the life in the tank. Both of these aspects will be addressed in this article.

Lumens
The basic unit of light is lumens (lm). This is a unit of luminous flux, which is a measure of the power of light perceived by the human eye. There are other ways to address this light flux, but for our purposes it can be thought of as the total amount of visible light emitted from a source. The more lumens, the bright the light will appear. It doesn’t necessarily mean that your tank will look brighter, as lumens does not take into account the direction the light is going.

Lux
The lux (lx) is derived from the lumen and is a measure of illuminance. This is the luminous flux hitting the surface. This is important because it is the effectively the amount of useful light. For example 1000 lumens spread over an area 1m2 gives you a figure of 1000 lux; however the same amount of light spread over a 10m2 area gives an illuminance of only 100 lux.

In short, illuminance is more relevant to lighting an aquarium than the luminous flux (lm) because this is a measure of light that can be in part applied to your aquarium. This figure will decrease the further from the source you get, and so when comparing different light sources the measurement should be taken at the same source.
This said, be aware that this standard of “Lux” applies to the visible light spectrum of humans and is thus is even more narrow than PAR.

Reference:
Aquarium Lighting; LUX

Spread
It is important to get a reasonable spread of light in your aquarium. This will allow you to view as much as possible and to get an even lighting effect. This can be affected by the type of reflector or lenses used on a light.

Color Rendition
The color of light used is critical if you want your aquarium to look the best. Reds will wash out under only blue light and similarly blues will not look good under red light. It is important to choose a light that picks out colors that you want to show. If you want luscious green-looking plants in your aquarium then a warmer white light will work well as it has more greens in the light.

Lighting Effects
Although spread is important, light and dark can be used in an aquarium to achieve dramatic effects. Think about varying light levels throughout your aquascape. Perhaps use a spotlight to highlight your favorite coral specimen. Or directed light to cast shadows in your tank. Remember you are making a display so think of it as lighting a stage.

Tips-
Always check the lighting requirements of the animals you are keeping. Some need lots of light to survive, while others prefer shaded spots.

Light to support life

Wavelength and spectrum
Visible light is actually a form of electromagnetic radiation that our eyes are sensitive to. This means that it can be thought of as waves of energy radiating through space. The length of one of those waves defines the color of the light and for visible light it is measured in hundreds of nano meter (nm). For example, violet radiation is about 410nm-440nm, the comes blue at 440-460nm. This continues through all the colors of the rainbow until we get to red at around 700nm. When these wavelengths are combined, different colors can be made.
For example 450nm blue and 700nm red would look like purple light to us, which is also known as CRI. What is worthy of note is that mixing of blue and red does not give you 410nm violet, RATHER the appearance of violet/purple.

When most of the colors are represented in fairly balanced amounts (particularly red, blue, and green), then the human eye will see it as white light. The amount of each color in a light is called it’s spectrum. A good spectrum will be as close to natural sunlight as possible which mean there will be light present from every wavelength throughout the visible spectrum.

PAR/PUR
Photosynthesis is a process that both plants and most corals use to turn light into food. This process allows these organisms to grow and flourish, and without the correct light energy they will die or with some marine animals that use this process for part of their food, they will simply not flourish.

PAR-(Photosynthically Active Radiation) is the measure of light within the range of wavelengths used by photosynthetic organisms (400-700 nm). It is measured in microEinsteins/m2/second. In physics, light is thought of as particles of energy, or photons. An Einstein is one mole of photons, where a mole is the number of carbon atoms in 12g of carbon (6.0221415×10^23).

Like illuminance, PAR measurements will decrease the further from the source you get, and so when comparing different lights the measurement should be taken at the same distance.

So, PAR is basically a measurement of the amount of light that photosynthetic organisms can use, and photosynthetic organisms include the plant and corals in your aquarium. This make it an important factor in choosing our lights. If you are keeping certain species that require a lot of light then you need high PAR levels. These doesn’t necessarily mean getting the brightest light you can, because the quality of the spectrum of light is important.
Some lights can provide broken spectrums which mean that although it is delivering high amounts of light in certain colors, it is lacking in others. The light may still appear to be white, but it may have serious deficiencies. PAR is therefore a partial but not complete indicator of what will work over your aquarium.

PUR stands for Photosynthetically Useable Radiation. This is even more useful than PAR as with PAR is what an organism can use, PUR is what it actually does use. Unfortunately, this is impossible to test for as it differs from species to species. It is worth nothing through that high PAR does not guarantee good results, but light energy within the known “spikes” of PUR is the better guarantee of results with less wasted energy.

Reference:
Aquarium Lighting; PUR
PUR vs PAR in Aquarium Lighting

The above article is MUST read article, since their is so much confusion being spread on the Internet about the importance of PAR and unnecessary PAR readings when PUR is more important

Photoinhibition
Unfortunately it isn’t quite as easy as just putting as much light as possible over your aquarium. There is a point at which light becomes damaging to plants and corals in that it actually reduces the ability to photosynthesise. Plants can get burnt and wither and corals can bleach. It is important that you recognize this when choosing your lighting and make sure you don’t over do it.

Lighting Penetration
As light passes through water it loses energy and is eventually absorbed completely. This means that it is important that the light you use has enough energy to pass through the depth of water for your tank you are trying to light.

Generally speaking this isn’t usually a problem unless you have a deep tank and want to keep animals that need high light levels at the bottom of the tank. Ways to ensure good penetration of light is to use very high power light (this method can be quite wasteful), or to focus the light to make sure that it reaches to where you need it.

Color Temperature
As light is absorbed by water it changes color because the lower wavelengths are absorbed first. This is the one of the reason that deep water can sometime look blue. This means that certain corals are adapted to more blue colored white light. Color temperature is a way to describe the color of white light. It is based on the color that a black body radiator will go as it is heated to very high temperatures and measured in Kelvin (K), which is a unit of temperature used in physics. So, at 3500K the white light is yellowy, like a standard light bulb. Natural daylight on a bright sunny day is considered to be 6500K. The more blue-whites that are good for keeping marine animals are at around 10000-20000K.

Reference:
Aquarium Lighting- Kelvin

Fact-
When changing lighting, you should expect a transition period where the plants and animals are adjusting to the new set-up. This can sometimes take a few weeks.

There are three main types of lighting that can be used on aquaria. Fluorescent, metal halide and LED.

Before the emergence of high power LEDs, the aquarist would have a fairly easy decision to make on whether to use metal halide or fluorescent lighting as they each have very clear and different advantages/disadvantages. LED light is now able to outperform these technologies in most cases, but there are still important considerations to take into account for each type.

Since LEDs are relatively new to aquarium lighting, but has taken the hobby by storm due to it’s longevity and practicality the remainder of this article will focus on different LEDs that are on the market today. If you would like more information on fluorescent or metal halide lighting, please see these additional resources.

Reference:

Aquarium Lighting- Complete facts and Information

If you would like some great in depth information specially about LEDs and their evolution in the aquarium world, please see this trusted source about the topic.

Reference:
LED Aquarium Types

With this aquarium lighting article, a great deal of effort has been put into to finding the best aquarium light on the market today. There is a handful of measures that are taken into account to make something the best. If you would like a great suggestion what what I think is the best light on the market, please take a look at this comparison chart that has been put together. It looks at some real contenders when it comes to aquarium light.
The chart shows pros and cons of each light. LED were the only lights compared in this chart, because as a standard, LEDs are becoming the best for aquarium lighting. Now, figuring out what LED is the best of the LEDs on market is the next step. I believe this chart will help guide many in the right directions.

PLEASE CLICK ON THE CHART TO ENLARGE

AquaRay, Maxspect, EcoTech, Taotronics, Evergrow, Al Sol, Kessil, LEDs; Aquarium Lighting Best LED

Comparison chart to show all pro and cons of major LEDs on the market.

Please note that as per the “true dimming” feature and requirement of fans by many if not most LEDs; this is based on the FACT most Aquarium LEDs still utilize the energy INEFFICIENT and HEAT PRODUCING “Current Reduction” Technology versus the VASTLY SUPERIOR “Pulse Width Modulation” Technology

Reference:
Aquarium Lighting; PWM
Aquarium LED Lights; PWM versus Current Reduction From this website

What is also worth noting is the Warranties, as most of the popular Aquarium LEDs are only warranted for one year, so in the end the bargain may not be a bargain when the LED fails in 3 years.
While a reader might think this is not likely; actual failure caused from excess heat, often the result from fan failure is quite common, since all LEDs but for the TMC require cooling fans due to their excess heat production which is a result of the technology used to drive/control their lights as noted earlier.

Further Suggested Reading:
LED Aquarium Lights, Lighting; How they work

Recommended Online Sellers
Based on product knowledge and up to date models sold (I do NOT recommend Dr. Tims):
AquaRay Lighting
These are the original Reef Capable Aquarium LEDs, with many upgrades since inception and original patents

Copyright 2015 by Steve Allen & Devon Trigg (Comparison Chart)