Reefs.org Forums

[EB847]

MY 150W D.E. RETRO KIT CAME WITH A 3/8" TEMPERED GLASS SHIELD. I MODIFED THE FIXTURE TO FIT INTO MY EXISTING HOOD. DUE TO THE SIZE OF THE HOOD, I REPLACED THE 3/8" GLASS THAT CAME WITH MY KIT WITH A CUSTOM 1/8" TEMPERED PIECE. MY QUESTION THAT NOBODY I HAVE ASKED HAS BEEN ABLE TO ANSWER IS: WHAT MAKES A PIECE OF TEMPERED GLASS "UV SHIELDED"? IS IT SOMETHING ADDED DURING THE MANUFACTURING PROCESS? IS IT A COATING? OR, DOES STANDARD TEMPERED GLASS SHIELD UV? THE PIECE THAT CAME WITH MY KIT HAS THE SAME STAMP AS MY NEW PIECE. IT SAYS NOTHING ABOUT UV. WHEN I ASKED MY LOCAL GLASS SHOP ABOUT UV SHIELDING, HE HAD NO CLUE WHAT I WAS TALKING ABOUT.

[Timbo]

UV protective glass can be purchased from a frame shop. It typically has an amber coating on it and is used to protect pictures from fading over time.

That being said, the UV shield that we used during testing did have a distinct amber tint to it. Unfortunately, Sanjay and I have not done significant UV testing and thus, I do not feel comfortable telling you if one sheet of glass would be safe compared to another. In reality, all glass filters out a significant amount of UV, be it conventional glass or UV protective.

The tempered nature of popular UV shields is a heat treating process that is done to protect the glass against failure due to the excessive heat that exists in the shield's operating environment. It does not affect the shield's ability to block UV, as far as I know.

Hope this helps you,

Tim Marks

[mkirda]

MY 150W D.E. RETRO KIT CAME WITH A 3/8" TEMPERED GLASS SHIELD. I MODIFED THE FIXTURE TO FIT INTO MY EXISTING HOOD. DUE TO THE SIZE OF THE HOOD, I REPLACED THE 3/8" GLASS THAT CAME WITH MY KIT WITH A CUSTOM 1/8" TEMPERED PIECE. MY QUESTION THAT NOBODY I HAVE ASKED HAS BEEN ABLE TO ANSWER IS: WHAT MAKES A PIECE OF TEMPERED GLASS "UV SHIELDED"? IS IT SOMETHING ADDED DURING THE MANUFACTURING PROCESS? IS IT A COATING? OR, DOES STANDARD TEMPERED GLASS SHIELD UV? THE PIECE THAT CAME WITH MY KIT HAS THE SAME STAMP AS MY NEW PIECE. IT SAYS NOTHING ABOUT UV. WHEN I ASKED MY LOCAL GLASS SHOP ABOUT UV SHIELDING, HE HAD NO CLUE WHAT I WAS TALKING ABOUT.

It is likely that the thinner one will be fine, but the only way to know for sure is to use a meter. I've seen several UV meters available for in-air use. Some of the easiest to find will be at your local sporting goods store. I recall them running between $25 and $50 each. Might be a good club purchase. I'd tend to purchase a full UV meter, if possible, rather than just one of the bands.

Regards.
Mike Kirda

[EB847]

THANKS FOR YOUR INFORMATIVE RESPONSE. IT'S FUNNY, I SEE PEOPLE ALL THE TIME WARNING THAT A SPECIAL PIECE OF UV SHIELDED GLASS NEEDS TO BE USED WITH D.E. HALIDES OR ELSE! MY KIT CAME WITH A STANDARD PIECE OF TEMPERED GLASS. NOTHING SPECIAL. I REPLACED IT WITH A THINNER PIECE OF TEMPERED GLASS AND HAVE NOT HAD A PROBLEM AT ALL. FURTHER, NO ONE HAS BEEN ABLE TO EXPLAIN HOW A PIECE OF SPECIAL "UV SHIELDED" GLASS IS MADE OR WHERE TO GET SOME. I WOULD LOVE FOR SOMEONE TO PROVE IT EXISTS, HOW IT IS MADE, AND WHERE TO GET IT. ALL THE GLASS SHOPS I HAVE TALKED TO ACT LIKE I'M NUTS WHEN I ASK.

[EB847]

THIS AUCTION STATES:

"* Do not mount "double ended" HQI type bulbs without a UV filtering glass shield!! This bulb will put out UV radiation which can damage your eyes and skin, as well as your animals in the tank. The bulb MUST BE burned behind a protective glass sheet."


http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... %3AIT&rd=1


I HAVE MY 175 DE BEHIND ONE 3/8" TEMPERED AND ONE .25" NON TEMPERED LID. NONE OF MY FISH SHOW ANY SIGNS OF SKIN CANCER.
JUST TO BE SAFE, I DOSE SOME SPF 45 EVERY FEW DAYS.

[FragMaster]

your not experiencing any ill effects in your tank because you "doubled up" on your glass . 3/8" plus 1/4" = 5/8".
It is now thicker than what you had to start with.
From what I have read recently all tempered glass shields uv,and all non temprered glass shields some as well, but the amount would have to be tested. SO effectivly you have double shielded your tank.

[vacuum]

HAve anyone used antiglare lenses? We supply coating equipment for sputtering antiglare on lenses.

[jaefei]

the coral color in the nature produced as ANTI UV from sun light. how if we give them UV so the coral color can be brighter ?