Reef photo period

[jhampton_wsu]

I've read some posts about this and I just had one follow up question. I currently have my VHO light on from 8:00am to 9:00pm. My 150w MH lights are on from 11:30am to 7:30pm. Currently the sun comes up around 7:00am and goes down at 4:30pm. My tank is in a room with a window but the window is not directly in front of it, more like 9ft across the room. Also, the room faces west so the sun comes up on the back side of my house. Any way, If I wanted to change my VHO periond to 9:00am-10:00pm and my Halide to 12:30am-8:30 pm does anyone think that the sun light coming in from the outside window would affect my coral growth or stress my fish? I could always just close the blinds but i'm just curious.

[ryshark]

I think the main affect you would get with the natural sunlight would be unwanted algae growth and possibly higher temperature.

[melosu58]

I agree with shark in that diffused sunlight will cause alot of nuisance algea in your tank. I would try to have a 12 hour or less photoperiod.