Mogal Metal Halide bulb direction

Interesting. I was thinking about the hollow tube area where the wire runs out to the socket. Thats the are that I heard needs to be up. My bulbs don't have a nipple in that part of the glass like in that article.

 

Actually mine do, as I guess they all do have the nipple. BUT is it more important to have that tube area at the top where the wire runs?

 

I see that is referring to HQI. What about single ended bulbs?

 

DE and Mogul bulbs are basically the same except the outer protective casing. Due to the mounts on DE bulbs, it does not allow you to change orientation.
HQI bulbs are available in both Mogul and DE. They should be effected the same as standard bulbs.

As for the tube that the wire travels through..... I have no idea. I am not a bulb designer, but I think the purpose of that glass tube is insulation. It would provide extra protection from an electrical arc from inside the burn chamber to that line. If this is the case, I can't imagine it's orientation affecting anything.

 

Look here guys.
Coralvue SE Bulbs | CoralVue

 

On my softy, LPS tank (standard 75 gallon) my bulbs were parallel. When I got access to a PAR meter and experimented, there was a HUGE difference when I put them perpendicular. Granted, that was with those reflectors which were not changeable because they were Hamilton fixtures with built-in ballasts. As you can see in the diagram, the PAR meter showed that I still had some weak spots even with 3 bulbs (however the 4 weak spots at the top didn't really have many corals in them).

 

Still the reflector and nothing to do with bulb orientation. If you had trouble getting coverage with 3 bulbs on a standard 4' long fixture, that is absolutely the reflector's problem. The reflector can make more of a difference to the PAR meter than the actual bulb.