get_armbarred
Community Member
I use a MH 250SE and notice some bulbs look worse than others when I change them. How do I know I'm not throwing away a perfectly good bulb? I would like to see what other peoples newly "burned up" bulbs look like.
What does a over used bulb look like?
- Thread starter get_armbarred
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MH bulbs have seldom reached the end of their life span when they are changed out in the hobby. Its generally accepted that the average span of use for a MH bulb is 9 to 12 months. This was based on a drop in par levels over that time period. I saw some interesting research done quite awhile back on the fact that lower the bulb closer to the water may allow enough compensation to make up for the drop in par, but haven't really noticed it go anywhere. MH bulbs will actually work for quite some time for other uses after they are taken out of service for an aquarium.
btkrausen
Fish Hoarder
I read on RC a few years back that some company would buy these used bulbs for use, as they really last many years after we are done with them. For some reason I'm thinking they used them for street lights or something like that. I'll try to find that info on RC for ya.
To answer the question, my bulbs after 12 months look very similar to them after just a few months. Usually you get the white around the edges, and the middle of bulb has a very light looking burnt mark.
To answer the question, my bulbs after 12 months look very similar to them after just a few months. Usually you get the white around the edges, and the middle of bulb has a very light looking burnt mark.
The only true way to know is to use a par or lux meter. You can't really go by look. I have changed out bulbs that I got at the same time and ran for the same amount of hours and one looked considerably more burnt or black than the other.
I have to find the article but also most of the drop off is in the first 3 months after that there is a smaller drop off in par until you hit like 18mos. I tested it when I ran Phoenix 250w 14k DE. I ran the bulbs for 24 months and experienced the same growth and color I did at months 9-12. I had no spectral shifts and no algae outbreak the people always seem to attribute to old bulbs. Dunno, just my .02.
I have to find the article but also most of the drop off is in the first 3 months after that there is a smaller drop off in par until you hit like 18mos. I tested it when I ran Phoenix 250w 14k DE. I ran the bulbs for 24 months and experienced the same growth and color I did at months 9-12. I had no spectral shifts and no algae outbreak the people always seem to attribute to old bulbs. Dunno, just my .02.
btkrausen
Fish Hoarder
Great points Paul. The other thing I wanted to bring up is the fact that I just changed my 150x Phoenix bulbs of 12 months, and saw no noticeable difference when the new ones went in. They looked exactly the same color and brightness as the older ones. Do you think this is merely something you cannot see with the eye, or the fact that these bulbs do last much longer than we give them? I think its like the oil change in your car...they recommend you change every 3000 miles, but its not necessarily required.
I forget the numbers but they were something like a 20%; drop off in par the first 3 months and then between month 3 an 18 there was only like an 8% drop off. I'll find it sooner or later. I also don't know about anyone else but I started to only run my bulbs for 6 months instead of 8 or 10. No drop off in growth, color or pe. I truly think the bulbs last much longer than we think but I'm no expert and can only go by my experiences. I tend to not take the word of anyone for an absolute in this hobby just because there are way too many factors that come into play like, bulb brand,reflectors,ballast, and many others that I am not mentioning because it is over my head. So generally when someone tells me something I usually test it out for myself before I believe them.
btkrausen
Fish Hoarder
From what the consensus on the forums say, they should be changed out every 12 months as well, but, as you've seen, that may not be the case. I say run them until they cause problems, or you see a reduction in growth from your corals.
Also depends on the ballast. If you run an Icecap 660 it overdrives the bulbs so you will be lucky if you get 12 months.
