Best DE bulb?

[guitareefs]

What's the best 250w double ended bulb with a crisp blue? That makes coral pop but provides great growth?

 

[DSC reef]

Check out Hamilton 20k. Great color and customer service is great.

 

[jda]

What ballast do you have? 14K Phoenix is fantastic at both on M80... no windex, but great pop and growth.