Because the lighting of your home aquarium system can be one of your most expensive purchases, it’s imperative that you take the time for all the necessary research beforehand. Aquarium lighting fixtures have developed more in the last 20 years than any other aspect of the home aquarium. Not long ago, “LED lighting” and “aquarium” weren’t commonly used in the same sentence. Now, LEDs have become the first choice for marine aquariums. But, in this article, we will review all of the most common lighting options for your marine aquarium. First, let’s take a look at a couple of the aquarium lighting basics.



Allow me to explain, the term “light temperatures” refer to the coloring of the bulb that you will be using. Light temperatures are not actual “hot or cold” temperatures nor are they directly related to the intensity of light the bulb emits. Degrees Kelvin is the unit used when measuring the temperature of a light. For example, a bulb that appears white with a slight yellow hint is a 6,500 Kelvin bulb. The higher the temperature, the bluer the light appears to our eye. It has been observed in many marine aquariums, corals often thrive and grow more successfully when placed under lights with a bluer tint. Therefore, a bulb rated at 20,000K will most likely produce the best results for growth of your corals. I personally prefer a nice mix of light temperatures, too much blue looks completely artificial. On the other hand, too much white inhibits the beauty and vibrant colors of your fish and corals. Aquarium light fixtures with 3 bulbs should have 2 bulbs at a temperature of 20,000K and one bulb at a temperature of 10,000K. An average temperature of 15,000-18,000K is ideal.



It has been said that 5-8 watts of lighting is needed for each gallon of your aquarium. These specs are unnecessary if you do not wish to grow corals in your aquarium. If you do wish to house corals in your aquarium than, 5-8 watts is just a standard rule of thumb. Less wattage may be required if you have a rather shallow aquarium or if you only intend to grow corals with minimal lighting needs. But, taller aquariums or those that wish to house corals with a strong thirst for light will need the higher number of watts per gallon. For example, a 125-gallon aquarium intended to grow a wide variety of corals will need something close to 1,000 watts of lighting intensity.

Unfortunately, corals can actually become “bleached” when they are put under lighting that is too intense. So, you can’t just purchase the biggest and baddest lighting system ever created and expect your corals to spread like wildfire. Keep in mind the depth of your aquarium, what corals you will keep and how much you have set aside in your budget for lighting.



The compact fluorescent option is probably the most basic option, anything below this (standard fluorescent) would be unsuitable for a marine aquarium. These are suitable for most corals requiring a low to moderate amount of lighting. These are relatively inexpensive fixtures to purchase. But, the bulbs need to be replaced every 6-9 months. We don’t recommend these types of fixtures to our clients. If a bulb is left in use longer than the recommended time, it will emit a light spectrum ideal for algae growth, not good for the health or appearance of your aquarium!


The T5 high output light fixtures are very popular among many beginner reef aquarists. The T5 bulbs are a good all-around lighting system which provide vibrant colors to encourage the growth of many corals including soft corals and LPS (Large-Polyp-Stony) corals. Some corals requiring higher intensity lighting such as SPS (Small-Polyp-Stony) corals can be kept towards the top of the aquarium, closer to the light. The T5 bulbs are not recommended for any aquariums deeper than 24”. These bulbs also last longer than the power compact bulbs, T5 bulbs need to be changed every 12 months. Any bulbs still in use after that time will only accelerate the growth of algae in your aquarium.


Very high output bulbs are less common than their smaller sibling, the high output bulbs. The reason for this is because they are a half step between the T5 bulbs and the next step up, metal halides. VHO fixtures are ideal for aquariums 24-36 inches in depth. All types of corals can be grown successfully in here. These unfortunately must be changed more often than T5 bulbs, VHO bulbs must be changed every 6-9 months.


Metal Halide light fixtures are some of the most expensive to purchase and to maintain but are well worth the return if you’re a serious aquarium hobbyist. First, we’ll start off with the cons of the metal halide lighting systems. These are very expensive to purchase costing several thousand dollars in some cases and the bulbs run upwards of $100 each. Metal halide light fixtures consume more electricity than any other home aquarium fixture, which in turn, costs you slightly more per month on your electric bill. Metal halide bulbs also produce the most heat, this could create a need for a chiller in your aquarium, another cost that you may not have budgeted for. Even though MH light fixtures are the most expensive, they do payoff. They are the most suitable to grow and cultivate happy corals of any kind in the reef aquarium. Fortunately, their bulbs last 9-12 months which is a bit longer than the VHO fluorescent bulbs. MH bulbs come in many different light temperatures ranging from 6500K to 20,000K. In an effort to minimize over excessive heating of your aquarium, many MH fixtures come with the necessary hardware to be suspended from the ceiling. You can also add glass tops to the top of your aquarium to decrease heat sensitivity, this will also aid in the evaporation rate of the water. Many die-hard fans of the metal halide aquarium light fixtures argue that this fixture produces the most stunning and rewarding views in all of the aquarium hobby.


Ah, here we are finally. The answer to all of your problems! LED aquarium light fixtures have quickly taken over the trade, so much so, some local aquarium stores have dropped all other lighting fixtures completely. LED’s have virtually no downsides but, some might argue the initial cost of LED fixtures is enough to drive them away. To this we say, Bah! Humbug! LED aquarium light fixtures have valiantly grown in the trade. LEDs quickly produced a large demand and, in turn, manufacturing competition was increased and the price was drastically lowered. Most LED fixtures are cheaper than that of their closest competitor, metal halides. Plus, the bulbs of LED fixtures last many, many years. LED aquarium light fixtures consume the least amount of energy whereas metal halides will create a noticeable increase in your monthly electric bill.

LED aquarium lighting fixtures have become such a popular niche that many savvy techs have begun to build their own DIY fixtures. Some have even started their own business built solely on the sales of their LED fixtures. Be wary of the reputation of these manufacturers. Some are excellent! Then there’s some that use the cheapest hardware and high-dollar words to trick you into purchasing a disaster. Consult online forums, local retail stores, or your local aquarium society or club for their recommendations if you wish to purchase from a local individual.



This concludes this portion of our DIY aquarium setup, evaluating the different aquarium light fixtures. As suggested before, do all the necessary research BEFOREHAND and you’ll be fine. Be confident and positive in your purchase and you can never go wrong. If you decide to purchase a used lighting fixture from a local venue such as a garage sale, Craigslist, Facebook or even a friend, always ask how long the system has been in use. Find out when the bulbs, if necessary, were last replaced. Be very cautious of purchasing homemade LED fixtures from anyone but the person who created it. If they cannot accurately answer your questions than they most likely did not do their research before constructing the light fixture.