Danger of Metal Halide?

[chanbi]

Hi, just join the forum.. And glad to know that we do for a club setup for marine!!

I have a question regarding Metal Halide. I was told there is a danger when using it (potential UV problem). But i seldom hear of it as a problem. Does most of the commercial lamp come with good protection (have attached a portion that i read in the web)? And btw, how often do we need to change the bulb? I have mine for ~8mths..

Problems with Metal Halide Products

Metal halide products also produce visible light and ultraviolet A and B. However, they produce an excessive amount of UVA, which can cause skin and other cancers. Metal halides produce less UVB - less than Zoo Med's reptile and iguana UVB-producing fluorescents. Because of the danger to humans, many of these products contain shields which filter out the UVA and UVB...so much so that they can end up producing too little UVB for use with reptiles.

Cheers..

[spiff]

u tokin abt HQI bulbs rite? only HQIs have uv problem, mogul base dun have.

as long as there is a glass sheild for ur bulbs u r save. uv is absorbed my glass so no danger

reaplacement if bulb is up to u. u may fnd tt there is a loss of intenstiy or a shift to the yellow spectrum.

[chanbi]

I'm not too sure whether mine is HQI? I bought it from Pacific Marine and it is made by Azoo (it is one of those that can be supported on a stand).

[spiff]

how r the bulbs supported?? by both ends or only 1 side.

both end means HQI......single end means mogul

i think azoo uses HQI bulbs

[Achilles Tang]

As long as you have the glass shield meant to filter out the UV rays... there should be no danger to humans, unless you intend to outstare a metal halide bulb!

There should be just enough UV for corals to react by producing flouroscent pigments to counter it... ie. get the beautiful colourful tips seen in SPS corals.

[ep4546]

just a question is will too much MH causes danger to the livestock whether coral or fishes

[Tanzy]

I don't think there can be too many MH bulbs over a tank! With the limited space over a tank it is impossible to provide more light than the sun can.

If you are worried about UV, as long as there is adequate shielding, it should be fine.

[ep4546]

u see i have a 2x 150w 13000k MH i am thinking of buying another one that is the same and place it side by side wonder whether the light will be too strong???

[robe]

In the US the norm for SPS reef tanks around 4 x 2 x2 is at least 2 x 250w and the majority with 2 x 400 watts at a distance of around 6 to 10 inches from the water surface. There's no glass cover some more.

[Tanzy]

No glass cover only for Mogul socket single-ended MH bulbs that have a UV shielding envelope. Double-ended bulbs MUST have a UV shielding glass cover for your health's sake because they lack one.