Improve coral and fish environments with aesthetically pleasing and functional light. World famous Radium Mogul-base Metal Halide Bulbs deliver brilliant blue coloration and significant PAR (Photosynthetically Active Radiation) values that support healthy photosynthetic corals and reef invertebrates. Single-ended Mogul (E39) base bulb is ideal for reef aquariums or any system that requires high light conditions. Maintain optimum aquarium light conditions by replacing old metal halide lamps. German made.
Visible Hue: Medium Blue
Application: Marine fish and corals
Ideal for: Hard Corals
Benefits: Blue-tinted light caters to the biological requirements of deep-water coral and the aesthetic appeal of aquarium fish.
250 Watt Radium works only with 250W M80 Ballast or 250W Electronic Ballast (does not light with M58 ballast).
400 Watt Radium works best with 400W M135 Ballast or 400W Electronic Ballast.
Handle bulb by socket end only, DO NOT touch bulb.
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Metal Halide Bulbs & Lamps.
Metal Halide Systems
Metal halide systems are high intensity discharge (HID) lighting systems popular among many aquarium hobbyists. Metal halide lamps generate a large amount of heat and also emit ultraviolet radiation which is harmful to eyes and skin. For this reason, metal halide discharge lamps require special handling and care to ensure safe and proper usage.
Metal halide lamps produce the most concentrated, most intense light of any type of artificial lighting. They are ideally suited for deep freshwater planted aquariums and saltwater reef aquariums containing light-loving corals such as SPS (small polyp stony) and LPS (large polyp stony) corals, and invertebrates including Tridacna clams, and others. A spectacular desirable effect of metal halide lighting in your aquarium is the "glitter effect," which replicates the effect of surface waves reflecting on a reef in a natural environment.
HQI systems offer many of the same features as conventional metal halide systems, but differ in design. The bulb is much smaller than screw-socket halides and is double-ended. Many of the ballasts for the metal halides can also be used for HQI fixtures. The HQI bulbs, however, require a system-specific socket. Wattage selections for HQI bulbs are commonly available in 150 and 250 watt bulbs.
Tips from our techs
What watt do I need?
150W - 175W: For aquariums up to 20" deep with mixed corals including a few SPS corals and clams placed high in the aquarium.
250W: For aquariums up to 30" deep with mixed corals including SPS corals and clams.
400W: For aquariums up to 48" deep or a dedicated SPS coral and clam aquarium.
1000W: For aquariums deeper than 48" with mixed corals or a planted aquarium.
Metal Halide Bulb Safety and Handling
- Metal halide discharge lamps should only be operated in enclosed fixtures with an ultraviolet absorbing glass filter (protective lens). Failure to do so may cause serious skin and eye inflammation. Do not use these lamps in any fixtures where any unfiltered light is emitted from the fixture. Do not operate these lamps if the ultraviolet absorbing filter glass is broken or uninstalled.
- Metal halide discharge lamps should only be operated in enclosed fixtures that safely contain all lamp parts in the event of a lamp burst or rupture. These lamps operate at a high internal pressure and at high temperatures. A lamp burst may occur, causing physical injury and property damage.
- Metal halide lamps should never be operated beyond their rated useful life. The risk of a lamp burst increases with lamp age, temperature, improper operation, and improper handling.
- Never bump, drop, apply excessive stress, or scratch the lamp. This could cause the lamp to burst. Do not operate any lamps with any traces of scratches, cracks, or physical damage.
- Never operate a lamp above or below its rated current or voltage. This could cause the lamp to leak or burst. Only operate lamp with compatible ballast and fixture.
- Always turn off the electrical power before inserting, removing, or cleaning the lamp. Avoid touching the lamp with your bare hands, and be sure to wipe off any fingerprints with a clean, lint-free soft cloth. Debris or oils left on the lamp can damage the lamp as it heats up.
- Electrical connections should be clean and in good condition.
- Replace the lamp holders and sockets when needed.
- Affix the lamp securely in the socket. Improper installations will cause arcing, overheating, and shorten life to the lamp and socket.
- Never touch the lamp when it is on, or soon after it has been turned off, as it is hot and may cause burns. Lamps should be allowed to cool for a minimum of 10 minutes after the lamp is turned off.
- Do not use lamp in close proximity of paper, cloth, or other combustible material that can cause a fire hazard and never expose operating lamp to moisture.
- Do not look directly at the operating lamp for any period of time, this may cause eye injury.
- Metal Halide lamps require several minutes of warm-up time to come to full brightness and color.
- Shut down period of 15 minutes per week is recommended for optimum lamp life.