Will Metal Halides Melt This?

[jonovan02]

I'm planning the lighting system for my new 80 gal tank and been reading about different refectors. This is what I've found:

"Mirrors are the only material that will reflect ALL of the light (no photons wasted)."

Here are my questions:

Do I wan't all of the light reflected into my tank? Or is defection better to scatter the light randomly?

and

Since I read that regular mirrors are not saltwater-friendly (toxic?), can I use a plexi-mirror (made of plexiglass) without my 2 175W metal halides melting them? Do i need to put the lights on a special bracket that will raise them off of the plexi reflector to aid the heat problem? If so, how far from the plexi do they need to be? Trying not to burn my house down. :lol:

 

[reefland]

"Mirrors are the only material that will reflect ALL of the light (no photons wasted)."

hmm. I seem to remember a study here showing a mirror wasn't a very good reflector for lighting tanks. Perhaps someone can dig up the link. I think it had to do with how the reflected light was spread.

 

[Len]

Not sure if this is what your referring to, but Sanjay is currently publishing reflector studies in Advanced Aquarist:
http://www.advancedaquarist.com/issues/ ... eature.htm

Reflector geometry is very important. While reflectivity is obviously important, the way the reflector is designed is just as imperative. Flat panel mirrors just don't cut it (scatters/wastes a lot of light). A polished aluminum reflector designeed to focus the light into a particular area is the better choice.

That said, halides won't melt the mirrors. I've used 250W halides 3-4" away from mirrors with no problem. You shouldn't need any special type of mirror since it doesn't come in contact with water (or at least it shouldn't )

FWIW, I'd go with one of the manufacturered reflectors anyday.

 

[Robin Goodfellow]

hi.
Heat from MH will melt acrylic mirror. Only option is aluminum and glass mirror.