How to Convert a Salt Aquarium to a Halide Light

Metal halide lights are classified as high intensity discharge (HID) lamps. Their extreme brightness makes them ideal for growing stony corals. However, the lamps draw a great deal of power (up to 1,000 watts per lamp), so be prepared for a higher electric bill after installing metal halides. There are kits available online at at some specialty saltwater aquarium stores, and these kits will make the installation process much easier, although they are more expensive than buying everything separately. If you are unsure about any of the electrical set up, you should seek the help of a professional electrician.

Things You'll Need

  • Metal halide lamps
  • Reflectors
  • 18-gauge wire
  • Ballast for metal halide lamps
  • Power cord
  • Cooling fans
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Instructions

  1. Planning

    • 1

      Determine how much light you will need. If you have a shallow tank (1 foot to 1 1/2 feet in depth), you can use a lamp with lower wattage. For deeper tanks, you will need more light. The greater the wattage of the lamp, the more light it will emit and the more power it will use. Lamps usually range from 70 to 1,000 watts.

    • 2

      Measure the space above the aquarium where you will place the lamps. You need to know how much space you have to work with. If you are fitting the lamps inside a premade hood, find out how much space you have under the hood for the metal halide lamps. Keep the lamps at least 8 inches above the water and away from the sides of the hood as they will get very hot when operating.

    • 3

      Select the type of lamps and reflectors. How you choose to mount the lamps and what reflectors you decide to use (if any) will determine the space you will need under the hood. Reflectors have shiny surfaces and are shaped like parabolas to reflect the light into the aquarium. They are much wider than the lamp so you will need to make sure you have room for them.

    Setting up the Metal Halide Lights

    • 4

      Purchase all the electrical equipment you will need. Make sure the ballast you select is rated for the type of lamps you will use. If you are not certain, ask the manufacturer or the store owner. Do not connect a metal halide lamp to the incorrect ballast. You will need wire that is rated for the voltage and heat of the lamps. An 18-gauge wire with SO or SJO type jacket to protect it from the water and heat is best.

    • 5

      Hang your reflectors in the hood. It is usually best to hang the reflectors a bit below the top of the hood to reduce the risk of burning it and so you can adjust the reflectors later.

    • 6

      Wire the system. Connect the wires to the lamp fixtures and connect to the ballast. Do not turn on the power. Make sure everything is securely fastened and away from the water.

    • 7

      Screw or snap in the metal halide bulbs into the fixtures. Do not touch the glass of the bulbs; the oil on your hands can cause the glass to crack when the lamp is on.

    • 8

      Install the cooling fans. You should use at least two fans if you are installing the metal halide lamps in an enclosure. One fan should blow air into the enclosure and the other fan, mounted on the opposite side, should blow air out of the enclosure. This will create consistent air circulation.

    Testing the System

    • 9

      Turn on the power to the fans. Make sure they are operating correctly before turning on power to the metal halide lamps.

    • 10

      Plug in the ballast and turn on the metal halide lamps. Make absolutely certain that all wires and your hands are dry and away from the water. Metal halide systems use high voltage and wattage and there is a real risk of severe electric shock.

    • 11

      Close the hood and check the lighting in the aquarium. Make sure the distribution of light in the aquarium is what you desire. You may need to raise or lower the hanging fixtures.