Life of a 400 watt de bulb

Hockeydad · 12/25/2006, 10:15 AM

What is the life expectancy of a MH de 400 bulb typically in hours?
Happy Holidays!

Nanook · 12/25/2006, 10:19 AM

This thread has been moved to the current forum.

ReefWreak · 12/25/2006, 02:32 PM

Depends on the color of the bulb. The lower the degree Kelvin, the longer it lasts, is my understanding. I believe the 20k and blue spectrum end bulbs tend to last only 6-8 months with full spectrum, and lose intensity and spectrum after that. I've read that 10k and lower last 12ish months. In Eric Borneman's "Aquarium Corals," he says:
"Metal halide bulbs may substantially change their intensity and spectra after approximately 1 year, and should be replaced after that time. Yearly changes have been a common practice in the past, though experience and some evidence seem to indicate that these bulbs can last significantly longer without being deleterious to the corals."

I've always wondered what the last part was meant to say, I guess that it's okay to keep old bulbs for a while. I'm running 250w 10k coralvue bulbs on coralvue electronic ballasts, and my acros are happy. BTW the bulbs are a year old, and I've been running them for a month now with no problems. I get good PE from acros, as well as good growth as well. I'm only going to upgrade to XM10ks soon because I want a bluer color without adding actinics, but that's a conversation for a whole different thread.

BTW to mods, I don't know if quoting like that is against TOS, or if it's copyright somethingorotherthatIshouldn'thavedone, but if it is, feel free to remove post.

12/25/2006, 10:15 AM	#1
Hockeydad Registered Member Join Date: Sep 2005 Location: Chicago Posts: 273	Life of a 400 watt de bulb What is the life expectancy of a MH de 400 bulb typically in hours? Happy Holidays! __________________ 120 gal. Euro design glass tank with three 400 watt PFO de and actinics. Closed loop Oceanmotion Super Squirt. 40 gal refugium, 120 gal sump. Knop/Geo reactors. All sps!! Current Tank Info: 120 Euro all sps

12/25/2006, 10:19 AM	#2
Nanook Ancient Eskimo Legend Join Date: Mar 2001 Location: Saint Louis, MO Posts: 41,852 Blog Entries: 11	This thread has been moved to the current forum. __________________ The wind blew, the chit flew, and then they came two by two. ~~~~~~~~~~~~~~ Current Tank Info: 375g Tanganyikan Tank & 470g mixed reef

12/25/2006, 02:32 PM	#3
ReefWreak Registered Member Join Date: Sep 2005 Location: Astoria, NYC Posts: 10,159	Depends on the color of the bulb. The lower the degree Kelvin, the longer it lasts, is my understanding. I believe the 20k and blue spectrum end bulbs tend to last only 6-8 months with full spectrum, and lose intensity and spectrum after that. I've read that 10k and lower last 12ish months. In Eric Borneman's "Aquarium Corals," he says: "Metal halide bulbs may substantially change their intensity and spectra after approximately 1 year, and should be replaced after that time. Yearly changes have been a common practice in the past, though experience and some evidence seem to indicate that these bulbs can last significantly longer without being deleterious to the corals." I've always wondered what the last part was meant to say, I guess that it's okay to keep old bulbs for a while. I'm running 250w 10k coralvue bulbs on coralvue electronic ballasts, and my acros are happy. BTW the bulbs are a year old, and I've been running them for a month now with no problems. I get good PE from acros, as well as good growth as well. I'm only going to upgrade to XM10ks soon because I want a bluer color without adding actinics, but that's a conversation for a whole different thread. BTW to mods, I don't know if quoting like that is against TOS, or if it's copyright somethingorotherthatIshouldn'thavedone, but if it is, feel free to remove post.