distance of MH to water

[scubaman]

I'm new to MH lighting and was wondering what a good distance from the bulb to the top of the water? I have about 7.5" from the underside of the canopy to the water surface. Is this to little by the time you attach the sockets , reflectors etc? I'm looking at 250w bulbs. I'm also worried about the safety of them (possibly exploding). Does it explode inside the UV shield or does the whole thing go, throwing glass everywhere.
Any help is appreciated.
Scubaman

[marietrg]

I'd like to know the answer of this too!!!

[MalHavoc]

When they go, they go. The exterior of the bulb gets very hot, and the cool water from your tank doesn't do that a whole lot of good.

You may want to look at these threads for information:

http://archive.reefcentral.com/vbulletin/showthread.php?s=&threadid=97175&highlight=bulb+distance
http://archive.reefcentral.com/vbulletin/showthread.php?s=&threadid=73970&highlight=bulb+distance
http://archive.reefcentral.com/vbulletin/showthread.php?s=&threadid=86219&highlight=bulb+distance

by the way,

[welcome]

[Mandoman]

I've always had the "distance" question, too. My MH(2-Ushio 250W 10K) are 9" from the water.

I have never heard of them exploding cept when you hit them with water while they are hot.

[Avonlea,PA]

Ok, I have 400W MH's. My canopy is 12" from water surface to the top, thus putting the bulbs about 10" or so from the water surface. Do you think this is too far away?? I'm not planning on having anything between the bulbs and the water, unless it's absolutely necessary.