Mogul vs. double end halide bulbs?

[captexas]

Anyone know if there is a difference in performace between single ended and double ended metal halide bulbs? I'm thinking of adding one retro 250watt halide to my 45g tank and I'm debating which one to get as there isn't much difference in price these days. Any input is appreciated.

[erikharrison]

HQI has more par per watt, SE has a better spread.

[Bill S]

Chris,

That's a tough question to answer. Right now I'm looking at making a change from DE to SE on my 400w - but that's more a function of bulb selection, which isn't very good on 400w bulbs. What I would suggest is that you figure out what bulb you want or want to look at, and then go and compare them over at Sanjay's site:

http://www.reeflightinginfo.arvixe.com/

[alton]

For me SE lamps retain there foot candles longer than DE.

[MissT]

DE are supposed to last a little bit longer, but the moguls have a ton of AWESOME bulbs

[hobogato]

also, i have heard that the SE bulbs are closer to their labled color temp but the DE bulbs are usually a lower color temp than they are labled. on my tank, my DE 12k reeflux are much less blue than my SE 12k reeflux - all are run on the exact same type of ballasts.

[erikharrison]

Ace, I have seen the same thing also occur with different balasts. One mag and one elec, same bulb, same age, burned in, different color! Also HQI bulbs last longer by about 6 months, possibly longer.

[caferacermike]

also, i have heard that the SE bulbs are closer to their labled color temp but the DE bulbs are usually a lower color temp than they are labled. on my tank, my DE 12k reeflux are much less blue than my SE 12k reeflux - all are run on the exact same type of ballasts.

I cannot fathom how this could actually happen. Not only do I work around halides all day long but I've seen how they are made. In reality if you look at a normal 400w halide pendant bulb (industrial warehouse) the inside is actually a DE bulb. The only real difference is that they don't surround the DE part with a UV diffusing glass shield. It is then up to the hobbyist to add UV protection. The outer envelope does nothing, nor contains no gasses, to help the color. The real added benefit of DE bulbs is that you can place more of them in the space occupied by SE. You might only be able to fit 2 SE over a space that you could fit 2 DE bulbs into. Not all bulbs are HQI nor are all ballasts. There is a difference if you compare them that way as they are being fired differently.

[captexas]

Thanks for everyone's input. I ended up ordering a 250watt DE retro kit as it fit in my canopy better between my VHO bulbs. As I haven't seen any DE bulbs in action, I decided to give the Coralvue 14k a try.

[hobogato]

i was told that the DE bulbs run hotter than SE and that is why they are not as blue as they should be. just hearsay.

i do know that there is no such thing as a 10K or 12K or any k bulb that is "true" to that specific color temp, since they all have colors that combine to get close to the labeled color.




I cannot fathom how this could actually happen. Not only do I work around halides all day long but I've seen how they are made. In reality if you look at a normal 400w halide pendant bulb (industrial warehouse) the inside is actually a DE bulb. The only real difference is that they don't surround the DE part with a UV diffusing glass shield. It is then up to the hobbyist to add UV protection. The outer envelope does nothing, nor contains no gasses, to help the color. The real added benefit of DE bulbs is that you can place more of them in the space occupied by SE. You might only be able to fit 2 SE over a space that you could fit 2 DE bulbs into. Not all bulbs are HQI nor are all ballasts. There is a difference if you compare them that way as they are being fired differently.

[ratboy]

I went from 400W SE, 14K over my "temporary" holding tub to a 250W DE, 10K and I must say the growth and overall appearance is much better with the 250W DE. The color isnt quite as nice (no supplemental actinics) but my few SPS actually have some nice color and my lps are fat and swollen looking. Im going to water test my 400 this weekend and if my repairs are good, Im going to pick up another 250 DE setup, throw on some T5 actinics and still cut my lighting power consumption by 1/3.