250 Watt 20000K Metal Halide Bulb - XM, Double Ended

MB6861

This item has been discontinued.

XM Lighting 250W 20000K METAL HALIDE DOUBLE ENDED BULB—XM

The XM double-ended 20000K metal halide bulb offers excellent coloration and good intensity. It is white with a strong blue tint. It brings out the fluorescent pigments in corals nicely. Fluorescent supplementation is usually not necessary, but can be used for added intensity and to simulate dawn and dusk. This bulb will work with standard magnetic ballast, magnetic pulse-start ballast, magnetic HQI ballast or electronic IceCap ballasts. It must also be housed inside a pendant. It cannot be used with simply a reflector in an open application as UV rays emitted by the bulb must first be filtered with a UV-proof lens. An excellent choice for  reef tanks 22"–30" deep.

Common questions/problems concerning metal halide lamps:
  1. Metal halide lamps of the same kind are different colors?
    Metal halide lamps operate by passing an electric arc through an arc tube that excites particles in the arc tube. When the metal particles reach an excited state they emit energy in the form of visible light. It takes 100 hours of operation before the metal particles stabilize and become a consistent color. All metal halides require 100 hours of operation before color and light output stabilize. All metal halides inherently have a slight color variation between individual lamps.
  2. The metal halide lamp fires and then either burns dull or the arc extinguishes?
    Usually the ballast and lamp are not receiving enough power. Metal halides pull a high current. Usually the problem is either there is too great a load on the circuit or the extension cords are of a small wire size and can`t handle the power needed by the ballast. Use only heavy duty extension cords and try running a ballast off a circuit from another part of the house.
  3. Do I need a cover shield between the lamp and the aquarium?
    Metal halide lamps produce a large amount of UV and also have a potential of exploding. The single ended metal halide lamps have an outer jacket which eliminates most of the UV. However, they have an inherent risk of exploding and UL requires metal halide lamps to be enclosed. On double ended lamps there is no UV shield. Double ended lamps must have a glass shield or major eye injuries including blindness may occur.
  4. Can I operate a ballast and lamp together which are designed for different wattages?
    Each wattage lamp and ballast are designed together for optimal performance and safety. If you over drive the lamp it may explode and shorten the life of the ballast and lamps. If you under drive the lamp it will also shorten the life of both components and also may explode. Do not mix different type wattages of lamps and ballasts.
NOTE: Double ended bulbs should always be used with the UV shield (supplied with most pendants). You and your corals can suffer from excess UV radiation otherwise. The bulb should be handled carefully as well since it has no outer glass casing. Using soft gloves is a good idea to keep finger prints off bulb. This is during installation and replacement.

Bulb Replacement Guide
Bulb Types Life of Bulb*
Normal Output Fluorescent 6-12 months
Very High Output (VHO) 6-12 months
Power Compact (PC) 9-12 months
T5 High Output (T5HO) 9-18 months
Metal Halide 9-12 months
LED (non-moonlight) ~5 years (50,000 hours)
* Manufacturer Recommendations
 




Manufacturer Info

XM Lighting
XM Lighting is the leading manufacturer of high quality metal halide lamps for the aquarium industry. XM Lighting began in 2003 and took the hobby by storm with high PAR levels, high quality lamps, and world class customer service. XM Lighting quickly became the hottest selling lamp in the industry, and they`ve continued the trend by developing new lamp wattages and color temperatures to meet the ever changing demands of the aquarium hobby.

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Overall, others give this:

  • 4.5

17 Reviewers (100%) would recommend this

Overall Rating:

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5  Star
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5
5.0
Great bulb

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REVIEW
The bulb has been installed only for a few days and it is bluer than my 14K Phoenix was. I am still waiting to see how well the corals take to the new light spectrum and if they color up a bit.
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5
5.0
Flawless Bulb

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REVIEW
Purchased this for a friends bio cube HQI. The 20k is a brilliant blue and gives the water a cool (temperature) appearance. Bulb fires up with no issue, and lasts a solid 8 months before the color begins to shift. Burn in time is around a week, and this product will not disappoint.
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5
5.0
250W 20K Bulbs

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REVIEW
these bulbs are just what I wanted- nice color and you guys had the best price on the internet. I'm satisfied.
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5
5.0
awesome

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REVIEW
I had the xm bulb before. When it was time to replace Itried another brand.It was too bright,not enough blue.My corals were hating life (not opening and shrinking)so I immediately ordered an xm. After being on for 2 days my corals opened and my zoo's are poppin.Awesome bulb and I highly recommend it...Read More
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3
3.0
Not for me

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REVIEW
I like blue but it's a little too blue for me. It not so much the blue that I don't like it's the darkness.. it's way darker. Growth slows way down. Some of my corals like pink lemonade did seem to get better color. The polyps actually turned pink. I'm running this on icecap and cheap Odyssea ref...Read More
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1
1.0
20000K Metal Halide Bulb - XM,

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REVIEW
Will not be buying this again. Surprisingly for 20000K the 'strong blue tint' isn't that blue and the worst thing about it, is that the porcelain ends are extremely fragile
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5
5.0
MH Bulb

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REVIEW
This is by far the best MH bulb hands down. You will not catch me with any other brand of bulb on my aquarium.
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Overall, others give this:

  • 4.5

17 Reviewers (100%) would recommend this

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