How to Select the Best Lights for Saltwater Aquariums
There are several different types of lights available for marine aquariums, and depending on the type of animals you are keeping, this can help determine what type of lights you need. Reef aquariums with live coral require bright, intense light with specific color temperatures so that the corals can photosynthesize. Fish only salt water aquariums require less intense light. Considering the lights can be a major component of your aquarium system, it's best to look at the different types of marine aquarium lights available. Lets take a look at How to Get the Best Lights for your saltwater aquarium.
Metal Halide:
Metal halide lights have long reigned as the king of reef aquarium lighting because of the bright intense light, full color spectrum and color temperature they provide. This has proven over time to be a reliable light source to grow corals under. Metal halide lights come in 2 different styles; Mogul, which has a screw in connector like a standard household bulb, or HQI, which has connectors at both ends and it snaps into a socket. While metal halides are great for growing corals, they do have some draw backs. The light bulbs must be changed every year, they consume a lot of electricity, and they generate so much heat, that you will probably need an aquarium chiller to keep the water cool, thus consuming even more electricity. While the cost to purchase metal halide reflectors, sockets, bulbs and ballasts can be relatively inexpensive, the cost to run and maintain them can get expensive really fast!
Fluorescent:
Fluorescent lights come in a variety of styles including HO (high output), VHO (very high output), PC (power compact), and T5. The most common types of fluorescent lights available on the market today are PC and T5. The fixtures are failer inexpensive, but the price can go up quickly the more bulbs that a fixture can accommodate. For a fish only aquarium or a refugium, a 2 bulb fluorescent light is usually sufficient. This does not require much electricity and is fairly efficient. Bulbs do need to be changed yearly as they intensity fades over time. Fluorescent bulbs can be used for reef aquariums, however it is recommended that you have a high wattage fixture that can accommodate anywhere from 4-8 bulbs or more. Some fluorescent fixtures have a combination of T5 and HQI metal halide for optimal coral growth. Most fluorescent bulbs are available in a variety of color temperatures which will provide different spectrums. You can mix and match as desired.
LEDs:
LED lights have grown in popularity over the past years and have come to dominate the aquarium hobby. This is because they are fairly inexpensive, and the LED diodes are designed to last for many years, thus not requiring yearly bulb changes. Combine that with low energy consumption and the fact that they will not over heat your aquarium water, and you have a very energy efficient lighting solution for your marine and reef aquarium. LEDs vary in price usually based on the intensity of the lights. Light fixtures with less intense LEDs are fine for fish only salt water aquariums and for refugiums. For live coral reef aquariums, you will want to go with the more expensive, and more intense LED lights such as Kessils or EcoTech Radions. Most LED lights are controllable and have either built in programming, or can be controlled remotely with an app or a LED light controller, giving you full control over the photo period, intensity and color spectrum.
Natural Sunlight and Beyond:
Some reef aquariums can be kept in natural sunlight, however this can present many challenges and is recommended to be left for professional reef keepers only. Examples of sunlight aquariums can usually be found at public aquariums in tropical regions such as the Waikiki Aquarium in Honolulu, Hawaii. New products coming to the market are E5 LED bulbs, which are flexible LED bulbs that can be used in existing T5 fluorescent fixtures, thus opening the world of LED lighting to fluorescent fixture owners at a reasonable price. Other types of lighting being experimented with for reef aquariums include HID (high intensity discharge) lighting and Plasma lighting. While these are in the experimental stage, a brighter, more cost effective alternative to LED lighting may be available in the future.