Reef Aquarium Lighting Types

Reef Aquarium Lighting Basics:

You know what type of tank you want; you know the highlights of various filtration elements; now it’s time to learn the basics of lighting (intensity, color, bulb choice, illumination time, etc.).

How you light your tank depends not only on its size, but also on what will be kept in it; however, properly lighting your tank does not need to be a complicated endeavor. Just remember that lighting should promote the health of your tank’s inhabitants and be visually appealing.

The corals and other invertebrates in your aquarium have to utilize the only energy source that is readily available to them: light. Energy is required to produce nourishment for your reef tank so enough light must be present to provide that energy. There are various options available when it comes to lighting; it is important that your reef tank be lit as strongly as possible relative to the space available.

Though lighting needs to be energy efficient for your tank, it also needs to be visually pleasing because, well, a reef aquarium is intended to be aesthetically beautiful. Blue lights (actinic fluorescent tubes and high color temperature metal halide lamps) are very effective in satisfying both of these needs.

Actinic lamps are exceptionally blue in coloration and cause many corals to bio-fluoresce, showing beautiful colors. However, to prevent your aquarium from appearing eerily blue, you may want to balance your lighting by using a 1:1 ratio with daylight lamps. Also, you can time the lights to simulate sunrise and sunset so that the tank inhabitants aren’t startled as would be the case if lamps were suddenly turned on.

Metal halide lamps don’t cause corals to bio-fluoresce, but they do produce a blue cast to the aquarium. To choose which lighting is best for viewing in your aquarium, you may want to mimic the lighting choice of an already-established aquarium that appeals to you; or experiment.

To gather detailed information on the various types of lighting, please select from the following links:

Reef Aquarium Lighting – T5, NO and VHO Reef Lighting

T5, NO and VHO Reef Aquarium Lighting

There are many options when choosing fluorescent aquarium lighting. The three main types of fluorescent aquarium lighting are Normal Output (NO), High Output (HO), and Very High Output (VHO). All of these fluorescents are linear in form, thus distributing light evenly across the water surface. Though HO bulbs are available as T12’s, T8’s, or T5’s, you will very rarely see one aside from the T5.

T12 = 1.5″ diameter
T8 = 1″ diameter
T5 = 5/8″ or .625″ diameter

T5 lighting was originally developed to be combined with specialized reflectors for the lighting of aquariums. T5 bulbs come in various sizes and are rather thin in comparison to standard fluorescent tubes and are more efficient. These bulbs were developed because traditional fluorescent bulbs couldn’t light an area more than 8-10″; below the bulb. Because of their efficiency and minimal heat output, T5 lights can be placed very close to the tank to maximize the light output.

Normal Output (NO) lights are standard wattage bulbs that come in various sizes and usually come with many stock aquarium hoods.

Very High Output (VHO) bulbs provide more lumens as compared to NO bulbs. All VHO bulbs are T12’s in diameter. VHO lighting generates less heat as compared to Metal Halides and will generally need to be replaced about every six months.

Reef Aquarium Lighting – Metal Halide Reef Lighting

Metal Halide Reef Aquarium Lighting

Metal Halide lighting is a type of lighting known as High Intensity Discharge (HID) lighting. Metal halide lamps are more energy-efficient than other lamps and are available in a wide variety of wattages and color temperatures. Wattage determines how much light is produced and color temperature determines the coloration that will be produced.

The higher the color temperature of a bulb (in degrees Kelvin), the bluer the light will be. Note: high temperature bulbs may not necessarily provide the best light for optimal growth and coloration in all corals. Also, metal halide lights may not be the best lighting option for smaller aquarium systems or where soft corals are the predominant coral kept.

With regards to aesthetics, lower temperature (~6500 Kelvin) bulbs may produce the most rapid growth and the greatest amount of total light, but the tank itself may appear drab with a yellowish tint. This is where the 1:1 ratio comes into play; adding some blue light will help to make the visual appearance of the tank as pleasurable as possible.

BE CAREFUL!!! Metal halides could burn SPS corals if the corals are not gradually acclimated to them. To reduce the likelihood of this happening, precautions should be taken. Your new corals should be (A) placed on the bottom of the tank and gradually moved up, or (B) temporarily screened from the light and gradually exposed to full light. Also, it may be necessary to run a chiller or fan to remove any excess heat that is produced from the lighting.

Metal halide bulbs should be replaced every 9-10 months (approximately 3000 hours of use). Don’t wait for the bulbs to burn out because, after 9-10 months of use, the bulbs will have lost thirty per cent or more of their elucidation.

Reef Aquarium Lighting – Power Compact Reef Lighting

Power Compact Reef Aquarium Lighting

Compact fluorescents, sometimes referred to as Power Compacts, are available in various intensities and sizes and are somewhat similar to standard fluorescents. They are similar in principle, but they incorporate two smaller tubes shaped like a “U” to produce a brighter, more intense light. You can install a retrofit kit into many existing standard fluorescent hoods/canopies to take advantage of the brighter light of compact fluorescent bulbs.

Compact fluorescent systems come in two lamp base styles: square pin and straight pin socket bases. The lamp base styles are not interchangeable so be sure you know which lamp base type your fixture requires before you purchase your bulbs. The most common base types used are:

1. 2-pin configuration
2. 4-pin straight configuration
3. 4-pin square configuration, often referred to as Panasonic or Japanese style

In comparison, compact fluorescent lighting is more energy efficient, producing more light output and lasting longer, than standard fluorescent lighting. Their bulbs are also smaller in size, so you’ll be able to install more bulbs into a hood or canopy. In general, most reef aquarium hobbyists use a combination of compact fluorescents and metal halide bulbs to illuminate their tanks.

Like standard fluorescents, compact fluorescent bulbs produce heat. When using multiple bulbs, you’ll need to incorporate adequate ventilation and/or a coolant system/fan in your hood or canopy. Regular use diminishes both the intensity and spectrum of the light produced by the bulb. Being the case, you’ll need to change your compact fluorescent bulbs on a regular basis (usually every 12-24 months).