Need a single 250/400w MH for 75, soon to be 225
 

As the title states, im upgrading from my 75 mixed to a 225 in a couple months. Right now the 75 has 150W DE Hqis that badly need new bulbs.

Rather than replacing the bulbs im thinking about buying a new fixture that will move to the 225 (31" deep) when the times comes. Im thinking a 250/400. This will be a single fixture on a lightrail.

A couple questions:
Would a single 400w DE on a lightrail bleach/shock my corals in the 75 after being under the 150's? I've heard people state that since the light source is not continuous that bleaching is not much of an issue when using lightrails.

What would be a good bulb to pair with a new Icecap ballast. I do have Icecap actinic supplementation also.

Thanks.

Somebody has got some opinions! :)

The light rail does help with bleahing but going from a 150 to a 400 you still might want to cut back the hours your light is on or raise it a little for awhile. I don't know a good lamp combination with the ice cap ballasts but I use the Galaxy/Radium combanation and love it.