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Metal Halide Lighting

Metal halide lighting are high intensity discharge (HID) lighting systems.

They provide intense illumination and are very popular and the fixture of choice to many aquarium hobbyists.

They are ideal for aquariums with ihabitants that require high lighting conditions.

They are relatively small in size and many of these new fixtures are well designed. So it has a space saving benefit as well.

A single fixture provids several hundred watts of light energy while other lighting systems require multiple units to provide the same light output.

It also adds a stylish look to any aquarium and even include lunar lights .

Have you ever seen aquariums that has those fascinating rippling and shimmering effects? Just like the sun when the water movement on the surface catches and reflects the light.

This effect is called “glitter lines”. And for aquarium lightings, metal halides are the only artificial light source that will do this so far. Yup, it's the only one capable of delivering these glitter lines.

They look amazing. You have to see it to realize how beautiful it is!

It gives the aquarium and it's inhabitants a more natural appearance like they have in their natural habitat.

You can accomplish a full amusement of your fish and corals in their colors as they would appear in the ocean.

Ok, I've listed a couple of benefits above. Now let's discuss the many options to consider before investing in a metal halide lighting.

First, you need to keep in mind what inhabitants you plan to keep in your aquarium. Then later decide on how bright the bulb should be.

The metal halide bulb is currently being sold in many different wattages and temperatures. The most common wattages found include 50, 150,175, 250, and 400 watt bulbs. The wattage basically will determine the brightness of the bulb.

Determining Proper Wattage

Selection of the wattage relates to how deep your aquarium is since the depth of an aquarium affects light penetration and light intensity.

• 175 Watt - Recommended for aquariums up to 20' deep or mixed corals with a few SPS and clams placed high in aquarium.

• 250 Watt - Recommended for aquariums up to 30' deep with mixed corals including SPS and clams.

• 400 Watt - Recommended for aquariums up to 48' deep or a dedicated SPS and clam aquarium.

Degrees Kelvin

There are also different types temperatures when choose metal halide lighting. It ranges from 4000K to 20000K. K is the degress Kelvin. Kelvin is the temperature reading used to rate the color of bulbs.

Saltwater reef hobbyists use bulbs in the more blue range (10,000-20,000 K range). A combination of florecent actinic bulbs as well as halides are often used to create a blueish look in the aquarium.

5500 degrees K is the equivalent of sunlight. The lower the degree K, the whiter or more yellow the lamp appears, the higher, the more blue the lighting appears.

Metal Halide Fixtures

Here are some of the metal halide lighting fixtures available to reef hobbyists today.

Aquarium Mount
- They are clamp-on lighting system for simple "plug and play" installation. They can be virtually mounted any aquarium or nano reef tank. Others are also made to be adjustable for easy positioning in the aquairum.

Pendant Lamps
- They offer simple, complete and innovative system. Most are encased with one bulb and come in a variety of sizes and wattages. These are very versatile in fixing above the aquarium.

Combo Hoods
- Combines metal halide lighting with compact and/or fluorescent lighting. Most manufacturers include a built in fan and UV absorbent filter.

Here is a Metal Halide Lighting Comparison Chart from Drs Foster and Smith which can help you choose which is the right one to invest on.

Bulb Replacement and Other Concerns

In general metal halide bulbs should be changed every six to twelve months depending on the bulb type and coral requirements.

Metal halide lighting is more expensive compared to flourescent.

But the main concern in using metal halide lighting is the amount of heat it generates.

You can use cooling fans to properly ventilate the trapped heat within the light fixture or canopy. If the heat is not properly taken cared of, not only that it will affect the performance of the fixture, the quarium water temperature will also increase.

So a big challenge when using metal halide would be the maintaining an acceptable saltwater temperatures. This is why positioning of the metal halide lighting is crucial.

A suggested 12 inches the water's surface is recommended. This way, adequate air circulation is acknowledged and will also help in minimizing the heat transfer from the fixture to the water. Hobbyist with a larger system use water chillers especially during summer.

To conclude, if you are the economic hobbyist type, just stick to flourescent lighting . But if you have the cash for investing one, stylish fixtures and breathtaking glitter lines awaits you!

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