MH bulbs

[midgetwaiter]

Originally Posted by Samw

Light Output of the Phoenix 14,000K DE MH Bulb Over Time

http://reefkeeping.com/issues/2007-04/ac/index.php

"The light output of the six Phoenix bulbs shows an initial decline over the first three to four months and then levels off at about 75% of their initial output. From these data I raise the question: “If a bulb is not replaced at six months, when it has lost 20% of its output, then why would we replace it at 12 months when its output has fallen only another 6%?” It may be more cost effective to plan the lamp number and placement based on 70-75% of the bulbs' initial output levels. "

"this bulb would appear to still maintain 70% of its output at 18 months, 66% at 24 months and 63% at 27 months of use. "

I hate this article sooooo much. It's a nice bit of work but people are completely ignoring why the author managed to get the numbers he did and IMO are going to big in for a big surprise when they try and duplicate the results.

He's using Ice Cap ballasts, this makes for a substantial difference in the bulb's useful life. You may be able to get close to this kind of life with other electronic ballasts but you sure aren't going to get anywhere near it with an HQI. 6 to 9 months with a Pheonix or Aquaconnect on an HQI and it's hosed.

They really need to make this point in the article.