Hqi lighting in north America

[Richard Adams]

Hello

This forums link was e mailed to me by a distant friend and I am quite impressed by its professionalism and I hope to learn allot from every one here. Question! We are now seeing more and more hobbyist turning there lighting systems over to Hqi from the standard north American Mogul based bulbs. Can you briefly explain what is the major difference between each and does one out perform the other. On a recent business trip to Hamburg Germany I notice that Hqi is all that is used over there from aquarium lighting to store fixtures is this just an old system now taken hold in North America or is there a significant difference

[EricHugo]

I can't really say why the switch - without the glass envelope, they are more powerful for the wattage, but you have to shield them, and usually with glass that gets salt crusted and dirty, and is thicker than the glass envelope surrounding a normal bulb. The bulbs aren;t really cheaper, nor are the fixtures. So, why the witch? Not quite sure...maybe because the fixtures themselves a smaller and thus a little more attractive over tanks?

[MalHavoc]

It's nice to see another Canadian on the forums. Welcome, Richard.

Just to make a point about the term "HQI". There seems to be a notion that HQI means "double ended", when it does not. You can have regular single ended mogul bulbs that are considered HQI. The term HQI is actually a trademarked term from Osram/Sylvania and stands for "high quartz iodide". HQI bulbs usually have one or both of the following characteristics:

1: They have a high CRI (colour rendition index)
2: They lack a starter electrode which means they need to be driven with a ballast that has a pulse-type starter.

There are a lot of Euro single ended bulbs that are "HQI", like the Ushio bulbs, the AB bulbs, and some of the Hamilton stuff.

[Richard Adams]

Thank both of you for the replies, I'm now a little bit smarter about hqi systems. Smaller they are and more attractive fixtures I think my future choice will be hqi.

Cheers and many thanks

Richard