how to tell if a MH bulb should be horizontal or vertical

[manopie]

Hullo folks! Been a long time since I posted here and all is well in la-la land . . . I think . . . heh

When my only good LFS went belly up this past year, I bought some lighting off of them, 1 MH (250W I think) with ballast, 1 compact fluorescent and 1, 4' T5 bulb .. . good price, couldn't pass it up -- the wife got a coffee and end table as my tradeoff . . .

Anyway -- onto my question (eventually I swear)-- The MH is set up in a poor vertical pendant style reflector but I was wondering if I could put my MH bulb horizontal -- in a new (and extremely better) reflector. There are no markings on the bulb whatsoever, and the ballast was built locally (I still talk to the former owners so I can ask where he got it) so I can't give you any info on the equipment itself. I could take pics of the bulb to see if the keeners amongst you can discern which bulb it is however!

Can all MH bulbs be placed horizontally or do they have specific directions they HAVE to be in?? I would like to place this horizontally and try to see how the bulb lights the tank but I don't want to damage anything in the process -- MH bulbs aren't cheap as you all know!

If anyone can help out it would be greatly appreciated - My tank is disassembled atm due to renovations ongoing in my basement so I'll be almost setting up from scratch again and I want to get this lighting mounted in a hood rather than from the ceiling if I could . . .

Thanks in advance!

Simon
AB, Canada

 

[Woodstock]

IMO, Horizontal is the best way to place a MH. Just remember nipples up... there will be a tiny bubble/nipple inside the MH. Also MH should be replaced after a year (some people go longer, some less).

 

[manopie]

Thanks for the reply Woodstock!

I looked at the bulb itself and I know where the nipple is so placing it up isn't a problem -- I was just worried that some bulbs couldn't be placed horizontally . . . I don't know how old this bulb is -- over a year for certain -- but I've also read that some MH bulbs can go longer sometimes 3 years -- the colour hasn't changed in all the time I've seen it in action (at the lfs and in my house) so I'll hang tight for now -- there's only lr in the tank -- well . . . the rubbermaid container -- sooooooo well that's all I guess! - time to get a new reflector!

Thanks again!

Simon
AB, Canada

 

[Woodstock]

You are welcome Upload some photos when you get a chance.

 

[UnderWaterParadise]

I think it all depends on the tank size IMO. My tank is 54x30x25tall so with that width I can use mine either way with good results. If you have a 18" wide tank Horz. is the only to get the best light coverage

 

[Boomer]

Simon

The MH is set up in a poor vertical pendant style reflector but I was wondering if I could put my MH bulb horizontal -- in a new (and extremely better) reflector


What are the numbers on the bulb. Some bulbs are Universal and can be mounted either way. Some are specific and must be mounted Vertical or Horizontal . Almost all the bulbs in this hobby that are Mogul based are Universal.


Doni
Just remember nipples up

Tha is a myth, except in some Horizoanl mount only bulbs, do to the more extreme curve of the plasma arch tube

 

[Woodstock]

Thanks Boomer.... What are the nipples for?

 

[Boomer]

Doni


They have no function really. The nipple is where they cut if off from the glass blower. Arch tubes are blown borosilcate glass.

In Horz only the Arch tube is often more curved . This can mean the the "soft silver metals" may not get all vaporized, as some of them may sit in the bottom of the arc tube. The Arch Tube is shaped like a "C" sideways, open part of the C down. The nipple is pointing up. If the C is upside down, open C pointing up, the nipple is pointing down. So the soft silver metals collect in the bottom of the curve of the arch tube. Here they can get cooled, do not vaporize well, thus less light output. The other bulbs often do not have his "more curve" to them.

 

[Gina]

I had heard also, nipples up! Good to know it's not exactly true. We were trying to put are bulbs in with the nipples up and couldn't manage to get it right so, we just left them as they are.

 

[Boomer]

Gina

Richard Harker go so upset with this that he wrote an article on it. Something like Nipple Up; A Myth. . I See will if I can find it.......................


The link also has Part 1
http://www.advancedaquarist.com/issues/mar2002/product.htm

 

[chris-miranda]

Thanks for the reply Woodstock!

I've also read that some MH bulbs can go longer sometimes 3 years -- the colour hasn't changed in all the time I've seen it in action (at the lfs and in my house) so I'll hang tight for now -- there's only lr in the tank -- well . . . the rubbermaid container -- sooooooo well that's all I guess! - time to get a new reflector!

Thanks again!

Simon
AB, Canada

3 yrs is way to long unless you run it for 1 hr a day most people change there bulbs every 12 months or less just my 2 cents

chris

 

[Woodstock]

Boomer: great info, thanks again!

Gina: as long as my corals/anemone get enough from these 15 K bulbs, I am never switching.

Chris: I agree. Even if the bulb is still burning after 3 years, the spectrum has shifted a lot.

Hummm... we need an "AGED BULB test". Testing bulbs at 100 hrs (2wks), 2,000 hrs(8mo), and again at around 4,500 hrs(1.5 yrs).

 

[manopie]

WOW -- what a response thus far! lol

Boomer -- there are NO markings whatsoever on the bulb itself -- it's a clear bulb - mogul socket -- that's all I know -- I THINK it's 250W but I could be wrong . . .

Very interesting info on the nipples up or down -- I'll try it anyway-- I have nothing to lose!

As for running the MH lights for 3 years - I'm only going on what I've read -- some people say the colour doesn't shift all that much for the life of the bulb, others say the opposite -- I take it all in with a grain of salt and go with what looks good on my tank usually (I have no corals but Aiptasia atm ;-D )

But otherwise I may just get my electrician to check out my ballast and see what's what and buy a new bulb when I get the tank up and running . . . someday anyway!

Thanks for the help and the info guys and gals!

Simon
AB, CA

 

[Boomer]

All bulbs should be marked or even the manufacutre does not know what they have. Look at the threads, are there any numbers stamped in ?

 

[manopie]

nada, nothing, zilch, zip . . . I can't find ANY numbers or anything -- anywhere . . . would a pic help? or do they all look alike? lol . . . not much help am I?!

Simon
AB, CA

 

[cheeks69]

Great info Boomer as usual ! I know with the XM 10k's some people were insisting that the reason some people were getting yellow hue was because of the nipple direction but IME they were just bad bulbs had nothing to do with nipple direction.