20K Ushio 400 watt MH

[Chris Lakies]

Has anyone used or seen the 20K Ushio's yet? I was wondering if they are a tad less blue or more blue than Radiums. Any Pictures?? Please post.

[PerryinCA]

They are about as blue when run on the same ballast, however, the Ushio seem to have more of a blue coloration as opposed to a bluish-violet to my eye at least. I would say that the two look very similar. When looking at the spectral signature, the ushio has a peak at 410, 450, 547, 575, and the radium has a peak at 450. The Ushio appears to have more actinic light according to some sources. All in all, it really is a close draw. Current research shows that increases in blue light lead to more blue coloration (reflection), so the radium may be a better bet for coloration. Although, as a standalone, the Ushio may give better growth. It's tough to tell without some good studies...

I would say that all together, they are pretty similar lamps.

-Perry
Sunlight Supply, Inc.

[Chris Lakies]

Thanks Perry,

Chris

[Hippopus]

I have four Ushio 20,000k 400 watt lights on my tank and I really like them!!! They are alittle more blue than the radiums. I am comparing my Ushios against a friend who just install 400 watt Radiums. Now he is using the PFO HQI ballast and I use PFO regulator ballast. I also use 2 400 watt 6,500 k sakis too! If I was just using the Ushios they IMO would be too blue-----I would use the radiums!
Jim