Photo period when switching to MH

Just received my new lights today and have them on my tank now. They are 48" MH 2x250W with moon lights. I had a 4x24W T5HO on it from my old 55gal while I was waiting. They are on a standard 90gal now. Just wondering how long I should have them on to start while my corals adjust, its a lot more intense light. My poor toad stool leather shrivelled up with in the first half hour.

 

just step up a half hour every two or three days... start at around 4 hours

 

Exactly--I just made the switch also. I did just as Dingo said. Started at 4 hrs and raised by 1/2 hr every 2 days. BTW I did keep my actinics at 11hrs.

 

You raising that new halide up a bit for the transition?

 

Thanks for the replies. I don't have any actinics on this fixture and I really don't want to start hanging things from the ceiling.

 

I used (wood) blocks between my last fixture and the tank when I did this last to raise it.