70W MH questions

[CodeToad]

I have been planning and learning about the 70W MH setup some of you have been using.

 

I notice many people drilling holes in their Regent fixtures, dosen't this let UV rays leak out?

 

Also how hot can you run these lights? Would it ruin it to have it in a small enclosed area with no ventelation? If it will ruin the bulb to do so, I was going to add a small cooling fan, but again wouldn't this let UV rays leak out that are harmful to you and your tank?

[ccny]

i'm a bit of a newb but FWIW i just did this for a 12 gal nanocube that i popped the hood off of about a month ago. the regent fixtures mostly come vented nowadays and the heat is not that much of an issue. i have mine just 5 inches from the water surface and temps are just fine (78-82) though evaporation is faster. i not sure what you mean by enclosed area. i wouldn't have this in a closed hood as i'm sure this will be an issue. for the summer, i might add an external fan blowing across the water surface but i'll see. uv leak isn't an issue because it comes with a reflector and glass to filter the light. the fixture case is pretty tough metal so adding a fan will be hard to do.

 

if i had to do it again though, i would go 150w with a higher k bulb than 10k. what i have now is ok for greyish leathers and stuff but for bright colored zoos and what not, my guess is you'd be better off with the 150.

 

HTH and good luck!

[qfour20]

I have a 70w metal halide in a regent fixture. I did not drill any ventilation holes, nor do I want to. The fixture itself is made to tolerate very high temperatures (halogen bulbs are HOT), so the metal halide is no problem in it (even with rustoleum high heat paint on the fixture). I cool the outside of the fixture by means of computer fans. Metal halide bulbs have a much longer service life if they are allowed to burn hot.

 

HTH

-q

[matt the fiddler]

"UV rays leak out?"

 

your only worrys shoudl be

 

1- direct light form the bulb [DE] hitting coral

2- direct light from the bulb hitting your eye [or reflection off the water could be an issue for an extended period of time...]

 

most of the holes i have seen cut have been away from either of these senerios-

[CodeToad]

Thanks guys. I was considering building a small wooden box to house the pendant inside a hood instelf with UV glass on the bottom only with no ventelation holes or anything. I guess that is a poor idea and I will stick with the Regent.

[bamann345]

DE or HQI bulbs need to be run a little warmer anyways. It isnt good to have a fan blowing air directly on the bulb.

[nanonut]

I have the 70 Watt MH on mine in the regent fixture no holes and it works fine. The 10K Ushio that's in it, is still a little to yellow for me even with 36 Watts of actinic. But it will do until I have enough money for an in wall tank. My dream! If the regent is working for you and you are happy with how it looks just leave it.

[CodeToad]

Well let me draw something up right quick... It's bad but I did it fast...

 

Say I were to make something like this, where the blue tube is the MH fixture and bulb. On top of the little box was UV glass that came with a regent fixture, and all 4 sides of the box were closed except a hole for wires, and the bottom is the bottom side of the canopy. Would this trap in too much heat for the bulb?

[matt the fiddler]

i would worry about the heat on the wood.. fire hazzard.. make suer your meterials can stand a lot of heat- if they are gogin to be with in half an inch from one of those bulbs

[USFnano]

You also wouldn't get much light spread if it was encased like that. Why not just mount it in a hood and use a piece of glass that covers the whole hood(I did this with my 10g, the glass was only $20)?

[qfour20]

Here's what I did:

 

http://www.nano-reef.com/forums/showthread...&threadid=29308

 

Hope this helps. By the way, I could have made the hood about 3" shorter, but I wanted the extra space to disperse heat. I live in texas, so heat is very much a concern for me.

 

hth

-q