Question about metal halides

[Justin0329]

I just picked up a new metal halide fixture. The unit is used and the previous owner doesn't recall how old the bulbs are. Im looking at replacement bulbs and I'm finding different styles and shapes. The bulbs that are in it are screw in but are shaped like a standard bulb (somewhat). The ones I like are more like a skinny cylinder rather than a bulb shape. Are the two interchangable? The wattage is the same and they are both screw in type bulbs. In addition, does one or the other work better? I'm sorry to keep rambling on but I really know little about these types of bulbs. Thank you for your help.

 

[Justin0329]

Does anybody know?

 

[Saratj1]

Usually metal halides are either what's called mogul or hqi based. The mogul is nearly the same as a regular light bulb (like e26 or something) except its threaded part is twice as big as a regular light bulbs'. The hqi bulb is about 4" long and shaped like a roll of quarters and has a metal post on each end that slots into the fixture(looks nothing like a regular lightbulb).
I have not seen a metal halide that looked like a regular bulb, that doesn't mean they are not around, I've only had a 250w aquarium metal halide, lowes has some that are lower wattage and for barn use that may be like that.

Hope this helps somewhat

 

[Justin0329]

what I am referring to are these two styles. are they interchangeable? Both are threaded what appears the same but I dont want to spend the money on something I wont have a use for.

 

[Saratj1]

All that matters is the size of the base , the glass doesn't matter. If its the same wattage (or even less wattage I believe ) your good.

 

[Justin0329]

perfect. thats what i was curious about. i appreciate it

 

[ccCapt]

While both of the bulbs you posted pics of have the same base, the one on the right is the type you want. The one of the left is typically a standard bulb that's used for outside lighting and is usually not the right color temp (K rating) for aquarium use. The rounder bulbs are usually in the 4000K-5000K range. You want a bulb that's more around the 15000K range and they are typically elongated in shape like the bulb on the right.

 

[Justin0329]

While both of the bulbs you posted pics of have the same base, the one on the right is the type you want. The one of the left is typically a standard bulb that's used for outside lighting and is usually not the right color temp (K rating) for aquarium use. The rounder bulbs are usually in the 4000K-5000K range. You want a bulb that's more around the 15000K range and they are typically elongated in shape like the bulb on the right.

Perfect! Thats the info I was looking for. I also wanted to make sure they both threaded into the same socket. Thank you very much for the clear and informative information!!!