Metal Halide Bulb UV Question

[Saltine]

Looking to replace my bulb, currently using 150w Radium 20k https://reefersdirect.com/index.php?id_product=354&controller=product and was going to continue to do so. Although I noticed this particular bulb referenced using a UV shield with it? I have no idea if my current lighting system has this, it's a http://www.marineland.com/Products/...-saltwater-reef-aquarium-lighting-system.aspx

Should I just continue using it without a shield or could this cause harm to the tank/family over time?

Thanks for any help.
Salt

 

[143MPCo]

The "UV shield" is the glass cover.

It also acts as a splash guard and keeps the bulb safe.

 

[Saltine]

The "UV shield" is the glass cover.

It also acts as a splash guard and keeps the bulb safe.

Ok, I figured but wanted to be sure. Thanks!

 

[mcarroll]

That fixture should have glass that came with it. Are the bulbs exposed when mounted in the fixture??

 

[Saltine]

That fixture should have glass that came with it. Are the bulbs exposed when mounted in the fixture??

No there is glass over the MH and plastic over the T5's.

 

[Saltine]

By the way it's a great fixture! Only thing I would consider replacing it with would be radions, other than that I don't think LED's can compare. I ran kessils/black box style.

 

[mcarroll]

Huh...

If you spend a lot of time in that room where the tank is, you might want to take action to rectify the UV situation – over time it will be dangerous for you. Especially your eyeballs. (You don't have to be looking at the bulbs.)

Either contact the manufacturer to see if you can get glass for it, get measurements to have custom glass made for it...or switch to LED's since it's about time for that anyway.

(I'm more serious on the first two answers...but upgrading to LED wouldn't be the worst thing you could do!)

 

[Saltine]

Huh...

If you spend a lot of time in that room where the tank is, you might want to take action to rectify the UV situation – over time it will be dangerous for you. Especially your eyeballs. (You don't have to be looking at the bulbs.)

Either contact the manufacturer to see if you can get glass for it, get measurements to have custom glass made for it...or switch to LED's since it's about time for that anyway.

(I'm more serious on the first two answers...but upgrading to LED wouldn't be the worst thing you could do!)

So you don't agree with others that the glass is the shield they are referring to?

Thanks!
Salt

 

[mcarroll]

You may have missed my 2nd post.

 

[Saltine]

You may have missed my 2nd post.

Well it does have glass over it, I just didn't know if it blocked the UV like it was supposed to or not

 

[143MPCo]

Metal halide (MH) lamps consist of an arc tube (also called a discharge tube or "burner") within an outer envelope, or bulb. The arc tube may be made of either quartz or ceramic and contains a starting gas (usually argon), mercury, and MH salts. Traditional quartz MH arc tubes are similar in shape to mercury vapor (MV) arc tubes, but they operate at higher temperatures and pressures.

MH lamps start when their ballast supplies a high starting voltage higher than those normally supplied to the lamp electrodes through a gas mixture in the arc tube. The gas in the MH arc tube must be ionized before current can flow and start the lamp. In addition to supplying the correct starting voltage, the ballast also regulates the lamp starting current and lamp operating current. (See "What types of ballasts are available to use with metal halide lamps?")

As pressure and temperature increase, the materials within the arc tube vaporize and emit light and ultraviolet (UV) radiation. A bulb (also called "outer jacket" or "outer envelope"), usually made of borosilicate glass, provides a stable thermal environment for the arc tube, contains an inert atmosphere that keeps the components of the arc tube from oxidizing at high temperatures, and reduces the amount of UV radiation that the lamp emits. Some MH lamps have a coated finish on the inside of the bulb that diffuses the light. Often a phosphor coat is used to both diffuse the light and change the lamp's color properties.

***Most manufactures add a glass shield to help with the UV on the fixture, if yours has it you are fine. ***

 

[Saltine]

Metal halide (MH) lamps consist of an arc tube (also called a discharge tube or "burner") within an outer envelope, or bulb. The arc tube may be made of either quartz or ceramic and contains a starting gas (usually argon), mercury, and MH salts. Traditional quartz MH arc tubes are similar in shape to mercury vapor (MV) arc tubes, but they operate at higher temperatures and pressures.

MH lamps start when their ballast supplies a high starting voltage higher than those normally supplied to the lamp electrodes through a gas mixture in the arc tube. The gas in the MH arc tube must be ionized before current can flow and start the lamp. In addition to supplying the correct starting voltage, the ballast also regulates the lamp starting current and lamp operating current. (See "What types of ballasts are available to use with metal halide lamps?")

As pressure and temperature increase, the materials within the arc tube vaporize and emit light and ultraviolet (UV) radiation. A bulb (also called "outer jacket" or "outer envelope"), usually made of borosilicate glass, provides a stable thermal environment for the arc tube, contains an inert atmosphere that keeps the components of the arc tube from oxidizing at high temperatures, and reduces the amount of UV radiation that the lamp emits. Some MH lamps have a coated finish on the inside of the bulb that diffuses the light. Often a phosphor coat is used to both diffuse the light and change the lamp's color properties.

***Most manufactures add a glass shield to help with the UV on the fixture, if yours has it you are fine. ***

Thanks for this, Great read....