View Full Version : uv shield????

04/07/2007, 01:27 PM
Hi I just stumbled on some info about a uv shield over metal halide bulbs. I was wondering how important this is. I have been running a ushio 250watt metal halide 10k at about 6" above the water I do not know if there is a problem doing this or not. Any thoughts???? Thanks

04/07/2007, 08:37 PM
Is your bulb the same as the one on this link: http://www.marinedepot.com/md_viewItem.asp?idproduct=MB6411?
If so, read the warning on paragraph #3.

Most of the "fried corals" reported by aquarists on this forum involve double-ended MH bulbs that went unshielded for a few hours. Nevertheless, here is a news article about eye damage resulting from a single-ended bulb similar to yours: http://www.msnbc.msn.com/id/17857910/.

04/07/2007, 09:28 PM
If it is a double end it must be shielded. Not only for your corals sake but for you own.

If it is a mogul base, the shield is built into the bulb. No shield is necessary.

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.

04/09/2007, 07:28 AM
It is a mogul base bulb. But it sounds like I should at least have a cover over it. Thanks