Question about MH DE vs. SE

[mcgrawjt]

Hey guys -

Just a question for my curiosity. Is there much of an output difference between metal halide double ended bulbs and single ended bulbs? 10 years ago when I started my 90 gallon I had a pair of single ended's over my tank, 4 years after that I upgraded to a 210 and put three double ended hqi pendants above my tank. The pendants are switchable from 250w and 400w DE bulbs. I had 250w ballasts and always ran 250w bulbs. I recently upgraded all three ballasts to switchable ballasts (250/400) and put in 400w bulbs.

The reason for my question is... when I was at 250w DE bulbs - my selection of bulbs was decent, now that I am using 400w the selection is quite limited for DE, but the selection is wide open for single ended bulbs. I'll admit when I was ugrading I went after HQI thinking it was the next big thing. Now I read that single ended bulbs (like the Radium) rival the output of HQI.

If that is true and there is not a huge output difference when my next bulb change comes around (about 10 months from now) I would switch the pendants out for SE mogul type pendants.

I would sure like to go back to the simple bulb change! It is a little nerve racking pushing the DE bulbs in the sockets, I have broken a few ends in my time.

Thanks.

John

[needmore-reef]

Have you read through Sanjay's MH bulb article? I belive its on the ReefKeeping magazine web site. Lots of great info on par ratings.

[t4zalews]

I switched from DE to SE and won't go back. The one main reason...options, options, options. Huge bulb selection and dozens of different reflector designs. I consider DE bulbs only good for all in one units where space is limited. But if you have a canopy or don't have an all in one unit, go SE for sure.

HQI is a very loosely used term when it comes to lighting. In theory, any bulb can be HQI, but may not be designed to run at a higher wattage. Output is only as important as the reflector used. Radiums are amazing, I went SE for Radiums.