[Bryan]

Originally Posted by pocilipora

I think there is something wrong with your Iwasaki side,thats way too yellow. Ive run the 250s, 400s, both Iwasakis, and the Ushio 400s. People would come over and think I was running 10K bulbs with the Iwasakis. Arent they a 6700K bulb? Should be alot whiter.IMO. Your ballast may be the cause, or is that a real old bulb?

The bulb is only about 3 months old. I suspect part of the problem is my choice of reflectors. Currently I am just using a sheet of flat stainless steel behind my bulbs. If you look around the area directly under the bulb it is bit whiter than the rest. I think a proper reflector wouldn't let the light bounce all over the place and concentrate the light in a 2x2 area.

Another point I have noticed is tanks with blue backgrounds will look whiter under the bulb than a tank with a black background.

Yes, I use carbon on a regular basis.