250w 10K DE or 250w 65k iwasaki

[rishma]

No, I don't want to start another endless debate about the merits of DE vs SE…. but I fear I might.

I have been a loyal 400w iwasaki user for some time, but my new smaller aquarium will incorporate one 250w supplemented with 28w PC's. I laboriously read most of the threads I could find on this and other boards, and I have a few remaining questions.

After reading Sanjay's AFM article on the spectral analysis of 250w lamps, I was convinced that my new halide would be a DE 10k 250w lamp. If I am correct, the data indicated that the PPFD/PAR values were higher than the 65k, thus a more effective use of my electricity bill. Some other threads called this assumption into question.

Is Sanjay's data a good basis for my decision?

Will his soon to be released study include some more data for comparison?
When will Sanjay's next article be out?

Finally, what is the expected useful life of the 250 DE bulb?

I typically change my 65k's every 14months or so.

Thanks for your facts and opinions.

Regards,
rishma

 

[golfish]

I'd say the DE's are good for at least 14 months. I changed mine out after 15 months and didn't notice a difference. I would have gone a little longer but I wanted to switch to the AB bulb.

It just depends on the corals you want to keep and the color you expect to get. I now use a 400 watt iwasaki and 2x400 watt Radiums. I didn't like the coral color or tank color I was getting from the Iwaskai and the 2x250 watt DE's. IME, SPS grow about the same under 400 watt Iwaskai, 250 watt DE and 400 watt Radiums. The color under the Radiums in most cases is better, second is the 10K then the Iwasaki.

 

[rishma]

golfish,

thanks for the reply. I am not really concerned about there color of 65k's. I am one of those guys who actually likes it. I am more concered with the performance and longevity of the DE 10k. I would just like some conformation that Sanjays data is correct -- the 250 DE bulbs have the highest PPFD/PAR outputs.

Why did you switch to AB bulbs? I know the fixture I am looking at comes with an Ushio bulb. What fixture do you have? Do you cool it with a fan?

Hopefully I can get a bit more chatter on this thread.

cheers,
rishma

 

[ChrisRD]

Rishma:

I get the feeling you'd get more responses on any OTHER topic, but most people are probably reluctant to post anything in a lighting thread anymore -

Some of our sponsors on the board who are LFSs (and very reliable sources of quality information) have made comments in the past that they have seen anecdotal improvements in growth rates and/or coloration when comparing DE lamps to SE lamps of similar wattage.

The testing and technical information that's been available thus far is confusing/conflicting at best. I'm guessing that as more information becomes available, we may find that the advantages of DE setups may have more to do with other factors (ex. ballasts, reflector designs, spectral output) than with the actual DE lamp style itself.

You might check out Rich Durso's website (this month's featured aquarium in Advanced Aquarist), as he has used several lighting systems on his tank and tracked/documented it on his site.