lighting cycle

[bonsai411]

I started off with compact florescents for my 90 gal (110 watts). However, wanted to upgrade the amount of light, so I buying a MH/PC combo, uping me to +400 watts total.

My question is the following. I was running the compact florescents for 10 hours. However, now that I am getting added blues with whites, how should I cycle this lighting system.

Should I do only blue for a few hours in the morning, then both blue and white mixed, then only white for the most part of the day, then back to a mix, then back to only blue for the nighttime?

If so, what hours should I do this for each step, and if not - what do you guys recommend.

Thanks in advance.

[acropora]

I'm not sure what you mean by adding blues and whites to your current P.C.'s. Are the blues actinics or lights closer to the 20000K range. You should be very carefull when you increase your lighting,especially when going to Metal Halides. M.H. have more intensity in a smaller area and will reach further down into your tank.Therefore you must decrease your photoperiod and/or raise up your lighting hood during an acclimation period.This period could be as long as one month, depending on your new lighting.

Most people run a 10-12 hr daily lighting routine.One method is to start off with your P.C.'s and have the M.H.'s come on a short time later(1HR).The PC's and M.H.'s will remain on together for most of the day. You can have your M.H.'s go off an hour before the P.C.'s and leave the P.C's on alone for the last hour.