Get Lighting Right the First Time. Reef Tank & Saltwater Aquarium Illumination | BRStv Buying Guide

Not all reef tank lights are created equal and there really is a myriad of things to consider when choosing the right light for your aquarium. Some of this may not be as obvious as you think such as the type of output or your general desires for aesthetics in the tank. What about your coral goals or long-term vision for the tank? All of this, and much more, is critical to making the best decision for lighting success.

Our BRStv Buyer's Guide to Reef Tank Lighting will first outline the four major categories or types of lighting you will choose from followed by a list of the most critical considerations so you can decide which matters most to YOU. After all, it is your reef tank and your success is what matters and we want to give you the knowledge to achieve that. 

LED's vs T5 vs Metal Halide

The very first decision is not much of a decision at all. With the advancement of LED technology in recent years, LED lighting is the smartest choice for 99.9% of reef tank owners. It's simply more efficient in terms of power consumption, does not require bulb replacements, doesn't transfer any heat into the water, and gives the user smart control.

While metal halide technology is pretty well antiquated at this point, you do see a small population of hobbyists still clinging to it. Truth is, metal halides look great over your tank, they provide a very natural spectrum and output, but are just not cost-efficient or practical over a modern reef tank. 

T5 fixtures are certainly the most viable alternative to LEDs. We stock a wide selection of bulbs and a few high-quality T5 fixtures. The diffused output they provide produces a wide spread of light that is difficult to reproduce with an LED fixture which some hobbyists feel is a better choice for their tank. The simplicity of not having to adjust the spectrum appeals to hobbyists as well, simply swap out the bulbs annually and you can be confident you're providing an optimized and proven spectrum over your tank. Using a hybrid of T5 and LED lights has become quite popular which gives the user the best of both worlds; most notably efficient operation and unparalleled light coverage.

The following information is universal and applies across all types of lighting with a heavy focus on LED lights because that is simply the choice for 99% of new tank owners. If you wish to learn more about the other types of aquarium lights, check out the Beginner's Guide To Saltwater Aquarium Lighting videos series linked below

Types Of Reef Tank Lights (based on output/spread)

  • Wide Angle Floodlight: A single-point source light that floods a large area with light at a wide-angle so it can be mounted closer to the water's surface. Creates a high-contrast appearance because it creates shadows with all of the light illuminating from a single source. Works really well for encrusting type corals that spread out. The small form factor looks nice and makes it easy to mount multiples together and cover a larger tank. This includes the popular EcoTech Marine Radion and Kessil A360X as well as your classic Metal Halide lamps. 
  • Narrow-Angle Floodlight (Elevated Lighting): Very similar to the above wide-angle floodlights in terms of form factor and applications but the angle of output is much narrower which requires a higher mounting height to cover the same area. Great for situations in which you want to mount the light higher up. Aqua Illumination Hydras and Orphek Atlantik fall into this category.  
  • Soft-diffused Light: T5 fluorescents and LED strip lights to create this kind of output. The perfect answer for SPS tanks or any kind of branching corals because it eliminates shadows by blanketing the tank in light that comes from multiple angles.  ATI Sunpower fixtures or the Reef Brite XHO LED strips to fall into this category.  
  • Hybrid - T5/Floodlight combos or LED strips alongside an LED floodlight which gives you the best of both worlds. The floodlight provides you with the power to penetrate and gives you that high-contrast appearance while the soft-diffused supplements help eliminate the shadows and fill in the gaps for an even spread of light. AquaticLife T5/LED Hybrid or one of the ReefBrite X-Series Hybrid kits can accomplish this. A hybrid light approach will ultimately provide the most effective coverage for mixed reef tanks and SPS dominate tanks. 


Directly, this is the maximum amount of electrical power the light can consume which directly reflects the strength of the output. More wattage = more output = more $$. With modern LED lighting, we see three distinct classes or groups of lights based on wattage: 50-watt range, 90-watt range, and 150-watt range. We can directly relate that wattage to coverage and cost. Not only does more wattage cost more upfront, but it also costs more to operate in terms of electrical costs. The trade-off is more wattage means better coverage and penetration over deeper tanks. 

For example, over a 48" tank I could choose to run four 50 watt lights or I could choose two 90 watt lights. Fewer fixtures mean fewer cords, less mounting hardware, and generally speaking an easier installation. You also have to consider paying for wattage you don't need; those 150-watt range lights are often overpowered for a mixed reef tank and would require that you tune it down. Then again, running your LED light at 50% power will likely result in a longer total lifespan.

  • 50 Watt Range - Most affordable and smallest profile, great for nano tanks and generally you are using one light for every 15" of tank length.
  • 90 Watt Range - The sweet spot for common aquarium sizes. Great for 24" - 48" long aquariums and you will typically need one light for every 24" of tank length. 
  • 150 Watt Range - These are the big guns designed for larger tanks over 48", SPS dominant reef tanks, or just more mature reef tanks that required heavy output lighting to get the coverage. One light for every 24-30" of tank length is typical

With T5 and metal halide lights, you're going to be using more electricity/wattage to achieve the same level of output when compared to LEDs. For the most part, T5 and MH fixtures use a fixed wattage bulb too. These are the general guidelines for choosing a T5 or metal halide fixture which then dictates the wattage. 

  • Metal halide - One MH bulb per 24" of tank length. 
    • 150-watt bulbs for tanks up to 15" tall
    • 250-watt bulbs for tanks up to 24" tall
    • 400-watt bulbs for tank up to 30" tall
  • T5 Lighting - Choose a fixture length that most closely resembles your tank length.  A 48" long tank requires a 36-48" T5 fixture and you will use the appropriate length/wattage bulbs in those fixtures. Example: A 36" T5 HO fixture only accepts 36" - 39 watt T5 HO lamps. 


Mounting options are important because aquarists are often limited by or just have strong feelings about the mounting options. The advice is to research the available mounting options for prospective lights and ensure those options will not only be compatible with your tank but will also be aesthetically acceptable to you. Every tank is different and you have to consider what it is going to take to get your brand new LED lights above your reef. Choose something that works for you. 

Can you suspend it from the ceiling?  Do they offer a tank mount or hanging bracket?  Does your tank have a rim or Euro-brace? Does it look nice or match your home decor?  Will it fit inside your canopy?  What kind of reviews does the mounting hardware get? These are the kinds of questions you need to ask yourself when it comes to mounting options.  Talking to other hobbyists or reaching out to our BRS Customer Service team can be of great assistance. Sometimes you just have to get creative and come up with solutions of your own if you have a particular situation that limits a typical mounting scenario.    


The shimmer occurs when light reflects off the surface of the water creating that natural-looking flicker. Exactly what you would see in the ocean as sunlight passes through the surface and onto the reef.  There is an entire range of shimmer you can choose from these days from something like the Kessil which produces a very strong, natural-looking shimmer all the way through something like T5 Fluorescent which produces zero shimmer effect. Most of the others fall somewhere in the middle. What level of shimmer do you like to see?


LED lights opened up a whole new door to control your reef tank lights.  Not only can you control the photoperiod and intensity, but you can also control the spectrum! This is a double-edged sword because it gives you the ability to produce something harmful to the corals too. Too much or not enough light is one thing, combine that with an insufficient spectrum and you are setting yourself up for failure.

BRS has gone to great lengths to help hobbyists set up their LED lights correctly. With our forgiving return policy on PAR meters and extensive catalog of LED lighting videos, there is no shortage of information.  Most of the LED manufacturers these days are also catching on and providing presets for hobbyists or even going as far as locking the spectrum to only allow minor (harmless) adjustments. Nonetheless, it is important to understand the level of control you are getting and what you will be up against when the time comes to turn the lights on! 

If you are not prepared to do the necessary research and take the time to set the light up properly, choose a light fixture that serves you something successful. The new Radion Blue or Red Sea ReefLED offers this easy-to-navigate spectrum control. T5 fixtures are easy in this arena as well, simply get the right bulbs, attach a classic wall timer, and you are all set.  

Lens Options

Some LEDs give you the option to add or change out the lenses. This could be as simple as a diffuser to cut back on the shimmer and better blending or something that will change the angle of the output. This helps you accommodate various tank sizes and shapes or focus the light to penetrate deeper into the tank where you need it.  While not all lights offer functional lenses, take the time to research your options or understand what the output will be based on the fixture's lenses.

T5 fixtures and metal halide lamps do not use lenses that substantially affect the spread or output of the light, they simply rely on reflectors to angle the output downward toward the tank. 

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