Are there 250W 20,000K Radium Bulbs?

[Wayner]

I have a standard PFO ballast that runs a 250W 6500K Iwaski bulb, do they make the 20,000 Radium bulbs in 250W, if they do, what can I expect with changing over to it, less yellow, even though I don't find the Iwaski that yellow, what benefits will I receive by changing?, will my acros colour up more?

Thanks

 

[rvitko]

Giesemann offers a 250w radium 20000k, the Tunze lamp is also a Radium lamp. I asked my customer his findings and he believes that the 20000k helps keep blue acros but he still has had some brown out. My personal belief is that from the photos i have seen acros grow in shallower water, and so the light could not be of such high K values in nature, though it does seem that certain colors are more prominent at different depths.