Help with upgrading my lights!!

[salt newbie01]

So here's the deal. The old set up was a 175 SE 14k hamilton, with the bulb sitting only 5-6" over the tank. Light period was 10 1/2 hours a day. New set up is a 250 SE radium 20k sitting approx 13" over the tank in a new canopy. I currently have three screens ( the white light diffusers from lowes) stacked on top of each other. There are three layers directly under the bulb then 2 layers then out to one as it gets away from the bulb. Right now I am only planning on running the bulb for 4 hours a day. And then gradually increasing the photo period and slowly removing the screens.

I am keeping various acans which are mainly on the bottom or off to the side and slightly shaded. I have micros which I had centered and up high - I left them where they were. I also have various zoas and palys. I left them where they were most are up higher in the tank. I just don't want to fry anything or bleach anything.

So does it sound like I am going about this correctly? Also how would you recommend increasing the photo period and removing the screens? Like which one first and how slow/fast to do so? Does it sound like I need to move any particular type of coral away from the light?

Any help you all can give would be GREATLY appreciated. I am really concerned I am going to burn everything!!

Thanks a bunch

 

[cee]

I think you're being overly conservative. You're going from a bulb with ~50 PFFD to ~70 PFFD, or about 40% increase (unless you're running HQI ballasts, but your post didn't say). However, your bulb is 2X+ the distance from the water. You're not going to hurt anything with your plan, but I'd probably cut the photoperiod only and do away with the diffuser or visa-versa.