Real world difference between MH bulb brands?

[stixx]

I am currently using Hamilton 250W 10K MH's. If I were to switch to say Ushio, would I necessarily see a change with my corals for example? Is there really a noticeable change with livestock depending on what type of bulb you use? Again, not in terms of bulb temp - strictly brand.

 

[kfowler]

Off hand, I would say yes. What one company calls a temp can be entirely different than another. For instance, I've tried an Ushio 14K and a Phoenix 14K. The Phoenix was much closer to a 20K while the Ushio was closer to a 10K. Not to mention all the other variables like PAR.