Lighting should one of the easiest things to get right with your reef tank, it doesn't have to be complex to get results. Still, reefers run into some huge challenges ranging from stressed out bleached tanks to waves of mortalities which are directly related to improperly implemented lighting.


Our goal through Episode #11 of the World Wide Corals and Bulk Reef Supply Hybrid Tank video series is building the light system for our tank to provide you with the fundamentals required to successfully light your reef aquarium.


SPS and LPS Corals in WWC Display Tank


What to expect with properly implemented lighting


Proper lighting will heavily influence both the biology and aesthetics of your reef aquarium and by proper lighting we mean the correct spectrum and intensity throughout your tank. The primary focus is always going to be the biological benefits of proper lighting but light is also what makes your tank look it’s best.


Biological Benefits

The right color and amount of light will support healthy metabolic processes which is evident in a coral’s general health, growth and even reproduction events. Corals also need usable light to produce fluorescent pigments creating that iconic rainbow of colors.


WWC 293 Gallon Display Tank


Pleasing Aesthetics

Light is what makes your tank look awesome and there are three reasons that have nothing to do with biology.


•The color of the tank is your eye’s perception of light reflected back at it so a wider spectrum of light will create a broader pallet of colors.


•Flat light, with minimal contrast does not create an impressive reef tank. The opposite of that, a million tiny specs of light often referred to as the disco ball effect, is just not appealing either. Finding the sweet spot somewhere in the middle is how you create a reef tank that really mimics what you would see out in the ocean and it has everything to do with the right lighting.


•Implement the light in such a way that compliments your tank and the space it is in. Choose a solution that looks nice to you and compliments your living piece of home decor. Some tanks are certainly more limited than others, for example, does your tank have a canopy or is it going to be open top? Do you have space to neatly hide and organize the cords?



Lighting Goals


Universally agreed upon goals

The lighting for our WWC/BRS hybrid tank was chosen to achieve four goals that we as hobbyists universally agree are necessary for successful captive reef aquariums.


Adequate Par

An average of 250 PAR throughout the entire tank with the understanding that the top section will always be brighter than the sides and bottom. It is impossible to achieve a perfectly spread 250 PAR throughout the entire water column. The minimum of 150 PAR on the bottom and maximum of 350 PAR near the surface will get us close to this average 250 PAR.


Difficult to shadow and diffused

This essentially means create and even blanket of light that is scattered and coming from all directions that seems to wrap around objects. This is less critical in the first year or two of the tank when the frags are small but particularly important when the corals are either close to each other or the colonies start to get large.


Proper spectrum for metabolic function

A proper spectrum for metabolic function and visual appeal. There isn’t a universally preferred spectrum range at this point but we do agree that a blue peak is required to support a corals biological function and energy requirements. Different areas in that UV, violet and blue spectrum will documentably change the corals fluorescence as well as the visual appearance.


Uniform Spectrum

It can be said that we know color spectrum matters and directly affects coral biology, related to that, we also have to acknowledge that providing a uniform spectrum is also a critical component.

The sun, T5 and metal halide bulbs emit a blended uniform spectrum that blankets the entire tank with a very uniform light spectrum. LED lamps, however, create individual peaks of color which need to be blended together to produce a uniform spectrum for both biological purposes and visually appealing aesthetics.


This blending can be achieved a few different ways with LED lights but the facts are, NO DISCO BALL EFFECT!


Consider those goals to be requirements for choosing our building your lighting solution. Outside of that, there are a few more important facts that need to be understood in order for you to then successfully implement your lighting.


WWC Bounce Mushroom


Facts to consider

Some corals fluoresce better under higher PAR

Not all but some corals will produce more fluorescent pigments at higher PAR ranges above the maximum 350 value we are shooting for. Rather than increasing the light for the entire tank, it is best to simply place those corals closest to the surface where light intensity is at its highest.


PAR Meter


PAR meters are expensive which poses a challenge

The biggest challenge to lighting a reef tank, specifically with LED lights, is the availability and cost of PAR meters necessary to measure lighting in your tank.


For modern reefers, the nature of LED lighting and the access to powerful controls makes it difficult to get the PAR right. Most reefers end up making the best educated guess which means some get it right and some do not, all with varying degrees of success in terms of coral growth and coloration.


A PAR meter costs $200 - $500 and is likely only going to be used once so we felt compelled to come up with a better solution and offer a PAR meter rental service. We are the only place offering this kind of service online and although it does require a deposit, $40 - $50 will give you access to a PAR meter for a couple of weeks to dial in your LED lights.


Randy taking PAR measurements


Stability trumps perfection

Corals are amazingly adaptive creatures and will thrive in all kinds of environments if you just let them. More important than getting everything perfect is just leaving them alone and not changing things. Corals thrive on stability more than perfection so your constant tweaks are 100 times more likely to produce negative results than positive.

If there is one thing to take away from this discussion it is don’t mess around with your LED sliders like a toy because this only inhibits your corals ability to adapt and thrive to the conditions in your reef tank.


AI Prime LEDs mounted on a light bar


Up for debate

In relation to the four lighting requirements, there are some things that still are debated with room for further discussion and exploration. Most of it being the best method of achieving any one of these goals or requirements.


What is the best PAR range?

This will probably be endlessly debated particularly the value of pushing the limits and going higher than our recommended 250 average PAR in as much of the tank as possible. The fact that you cannot achieve a perfect distribution of PAR and will likely always be creating a variable range is also something to consider here.


BRS Lobby Tank Radion Lighting System


What is the best way to get evenly diffused and blended light?

The easiest method of doing this is absolutely a bank of T5 fluorescent lighting which effectively blankets the entire tank in light. Second place is metal halides with large reflectors to reflect light from various angles into the tank.


LEDs are a different animal altogether. In terms of shadowing and diffusion, it is really only poses a major problem for mature SPS dominant aquariums. Softy, LPS, or many mixed tanks, this just isn’t as big of a concern because the shadows are generally not detrimental to the health.


With that in mind, there are four ways to achieve a more evenly blended output when using LED lights.


•Raise the fixtures higher; as LED light travels further away from the point source the light spectrum becomes more evenly blended.


•Use multiple lower wattage fixtures as opposed to a single high power fixture. The overlapping of spectrums from the fixtures creates more even coverage and reduces hot spots.


•Use panel type LEDs like the Orphek Atlantik with individual diodes spread over a large board which results in something similar to T5 coverage.


•Use diffusers such as the Radion Diffuser from EcoTech Marine. This diffuser material blends the light spectrum very effectively but also reduces intensity to an extent.



EcoTech Marine Radion Spectrum


What is the best spectrum?

This is perhaps one of the biggest debates in the LED lighting realm. T5 and Metal Halide lights offer a variety of proven spectrums that have achieved great results.


With LEDs, manufacturers give you complete control over both intensity and spectrum which gets reefers into trouble. Many reefers simply adjust the output until it looks good without regard to coral biology, health and coloration. The result is often slow growth, loss of color or even mortality.


Dana Riddle did a MACNA talk called HELP! My corals are changing colors and demonstrated how violet and UV light can turn some green corals red. You can find numerous accounts of hobbyists discussing the effects of the red spectrum and how it can slow photosynthesis or even bleach corals.


Orphek has some excellent research all about how various pigments within corals use light energy. Check it out!


Chlorophyll and carotenoids within corals prefer very specific spectrum wavelengths. Most agree the ideal spectrum peaks should mirror the chart above. You can see that if the spectrum moves just 10-15 nanometers in any direction, the ability to use that energy falls drastically.


The most important message is spectrum matters and it matters significantly. Manipulating the spectrum can and will affect the corals in your tank.


Adjusting Kessil LED lights using Kessil App


How to find the best spectrum?

Some reefers do have a solid understanding of spectrum and how it affects corals but it is not something as thoroughly documented as various other aspects of reefkeeping because it is still not widely understood even by scientists. Even with the appropriate understanding, obtaining the right tool to measure and adjust spectrum at home is costly and out of the question for 99.9% of reefers.


A few manufactures, however, are leading the way in terms of making high quality light fixtures and providing users with the necessary information for success.


Kessil did this correctly right out of the gate with their Kessil Logic in which they give users the ability to adjust the spectrum for visual appeal without ever going outside a suitable color spectrum.


EcoTech Marine is doing excellent things to progress the hobby by including very specific spectrum suggestions based on tank type and also works with industry leading coral wholesalers and aquaculture facilities to study and further explore this topic with their CoralLab projects.


Orphek Light Spectrum Diagram


Orphek is another company providing direct settings based on tank type and has published substantial research on the topic of lighting for corals. In fact, the news section of their site probably one of the most extensive catalogs of coral lighting research available online.


Spectrum blending, why does it matter?

Historically, spectrum blending wasn’t really a topic for debate because T5 and Metal Halide bulbs provided such well blended spectrums that is was not even an issue. With the use of reflectors the light is further blended and spread over your tank to create very even coverage and full spectrum light.


Properly blending these LED spectrums is not an overtly simple task and the importance of this was overlooked in the initial phases of LED light application on reef tanks. Most of the efforts were simply focused on using wide angle lenses and hoping the spectrums overlapped enough to create an appropriate blend.


Wide angle lenses are adequate in most cases but as you go deeper into the tank these spectrums start to fluctuate because of light refraction from the water’s moving surface. This is evident to the human eye with what many call the “disco ball effect” and most will agree it is ugly and undesirable in terms of coral health.


It is fair to debate exactly how much this dancing spectrum matters in terms of coral health. So long as the coral receives the same net amount of a particular spectrum photons, does it really matter? Ultimately, probably not but that assumes this is done well and that corals are not getting blasted with high concentrations of specific light colors.


The best ways to create an evenly blended spectrum are as follows:


•Raise the lights up higher; LED light blends more evenly as it travels further away from the source.


•Use a diffuser which effectively blends the spectrums together.


•Supplement the LED with T5 fluorescent which is a very effective method with great results


•Buy an LED light that houses all of the diodes under a single lens like Kessil



WWC Flower Anemone with Logo


The World Wide Corals (WWC) approach

Lighting is complicated and even more so when it comes to using LEDs over your reef. Let’s take a look at what one of the industries leading coral aquaculture facilities, World Wide Corals, is doing to overcome the challenges of LED light.


WWC 900 gallon display tank lighting system


900 Gallon WWC Display Tank

The flagship tank is lit with a grid of Radion XR30w fixtures with each covering about 2 square feet. They are also supplementing with three rows of T5 fluorescents all of which is mounted 20.5 inches from the water’s surface.


The photoperiod is a 12 hour modified AB+ Radion schedule with higher intensity fuller spectrum in the morning and a lower intensity blue spectrum throughout the remainder of the day with very limited ramp up and ramp down time. Here is a link to download the complete Radion schedule for EcoSmart Live.


WWC EcoSmart Live lighting schedule downloadable template


The T5 fluorescent lights are on for 8 hours through the middle of the photoperiod. Keep in mind the overall intensity is tuned to achieve the desired PAR and if you plan to mimic this at home we still recommend the use of a PAR meter to achieve these results in your aquarium.


WWC goes to great lengths to achieve even and consistent PAR values which was evident in our PAR testing. Most all of the PAR readings we took landed in the 150-350 PAR range through the entire 900 gallon tank.


WWC 500 gallon display tank


500 Gallon WWC Display Tank

In the 500 gallon display WWC is using the same Radion and T5 mix but the hood negotiates the mounting height at 16” from the water’s surface in this case. This results in a just a few hot spots but overall very evenly distributed compared to many LED lit aquariums.


The overall PAR values are just a bit higher in 200-400 PAR range which they attribute to being able to add significantly more flow in a tank of this size. Many agree that the higher PAR and flow rates are producing a bit better coloration but Josh from WWC will admit they are riding the edge and this tank does require a more watchful eye.


WWC 293 gallon display tank


293 gallon Mixed Reef Display Tank

The mixed reef tank has a bit different approach with six Radion XR15 LEDs with the diffuser accessory which allows them to mount the lights much closer at around 13.5 inches from the surface.


The overall PAR is a bit lower in the 100-200 range and the grid of diffusers is doing an excellent job at blending and distributing the light over the tank with no discernible hot spots.


In episode #2, #3 amd #4 Randy went through an in-depth review with Josh from World Wide Corals about each of these display tanks and if you wish to learn more, be sure to check out those videos. Better yet, forget Netflix for a night and sit back with your favorite beverage and binge the entire WWC/BRS Hybrid series.


BRS Office Tank


Bulk Reef Supply (BRS) preferred methods

World Wide corals has developed a very simple and stable approach to lighting. Here at BRS we have years of experience in the lighting department which results in very similar goals and results as WWC with the difference being here at BRS we work with tanks that are in the home or office.


We all believe in large sources of diffused light for show stopping SPS tanks. With our video BRStv Investigates: Setting a baseline for SPS corals and future lighting tests we came to the conclusion that 250-350 PAR in as much of the tank as possible is the sweet spot and almost identical to what WWC is doing.


Due to common realistic budgets most BRS reefers are using T5s to achieve widespread diffused light or T5/LED hybrid solution to get extra color and shimmer. Most of the tanks are at home or in the office and operate without hoods so mounting height is a bit lower compared to WWC and typically within the first 10 inches.


Just like World Wide Corals we have not had a single LED only mature SPS aquarium here at BRS. Mostly because it is a lot more expensive to properly light but also because it is much more work to get it just right and acheive the widespread even PAR numbers you need.


WWC lighting requirements


The BRS/WCC hybrid method

The goal with our hybrid system is take the knowledge and methods from each and combine them to create a successful approach to lighting a reef aquarium that works for any reef tank and any hobbyist. WWC corals uses simple and stable lighting systems combined with meticulous husbandry to grow the jaw dropping corals they are famous for.


BRS lighting requirements


At BRS we focus on reef tanks for the home or office which is exactly what 99% of you are keeping and this alone creates some additional requirements over the larger scale commercial environment at WWC.


Lighting requirements summary


With all this considered, if you follow these rules for lighting you will be successful or at least you can be 100% certain lighting is not an issue.


The best looking tanks using technology available to reefers today are being lit with diffused LED lights or a T5/LED hybrid solution

The reason is because these solutions give you that even blanket of light throughout the entire tank which pretty much sums up everything we have documented. Smooth even coverage with a proven spectrum and PAR range of 150-350.


Tank types defined


To fulfill the requirements for offering systems that works for anyone, we came up with three different types to accommodate different situations. You can apply this logic to other tanks sizes but the following suggestions are intended to be for a 4ft long 120 gallon aquarium which is a common size aquarium for SPS collectors.


Low Cost Lighting - Budget friendly with solid results


•6 or 8 bulb Sun Blaze T5 Fixture


Metal halides (reflectors, 250 - 400 watt ballasts and appropriate bulbs)


Aquatic Life Hybrid using x3 Aqua Illumination Prime LEDs and ATI Blue Plus T5 bulbs



Common Lighting - Balance of cost and features


Aquatic Life Hybrid using x2 Kessil A360X and ATI Blue Plus T5 bulbs


•Eight Aqua Illumination PRIME LEDs mounted 12” or higher from the surface


•Two Orphek Atlantik Gen 2 LEDs mounted 16” from the surface



High End Lighting - Expensive with real advantages


•Six EcoTech Marine Radion XR15 lights with diffusers



BRS Lobby Tank


BRS Office Tanks


Lobby Tank

This is a six foot long aquarium located in our main lobby so it has to look amazing. We chose x10 of the Radion XR15s with diffusers. It may sound like a lot but it is essentially equivalent to x5 Radion XR30s which is fairly common over a tank of this size. By going with the x10 smaller XR15s we get more options for spacing, mounting and individual controllability.


We have to admit Radions essentially win by default because there really is no other diffused LED light options that eliminate the disco ball effect altogether.


Red Sea E170 aquarium


Red Sea E-170 Aquarium

Low cost is a big concern for this aquarium and it comes with an Aqua Illumination Hydra TwentySix. So it makes sense to use that LED light and pick up a low cost T5 hybrid solution to even the light distribution and soften the shimmer for an aesthetically pleasing result.


For those of you with a similar size tank but don't already own a Hydra TwentySix LED, the Orphek Atlantik panel LED would be an excellent LED only option.


52 weeks of reefing BRS160


BRS160 - 52 Weeks of Reefing Tank

Many of you already know what is lighting this tank because of our popular 52 Weeks of Reefing video series. We are running five Kessil A360 LED lights with four 80 watt T5 bulbs. Since Kessil has the new A360X LEDs which offer wide angle lenses, more color options and better controllability we swapped out the original Kessils with the new A360x and be sure to check out the BRStv Investigates for a full review.