lights power consumption

[BMW Rider]

Well, the power bill just arrived again. I can't believe how much it keeps going up. I figure my new reef tank is using over $60 / month most of which must be for the lighting. This is about $20 more than I figured as a maximum when I set it up. I'm trying to figure out just how much I need to run the lighting to be ok. Currently I'm running two 96w PCs for 12 hours and two 250w MHs for 11. I'm wondering if I can drop them down to 11 for the PCs and 9 for the MHs. Will this be a long enough photo period for the corals? Alternatively , do I need to have the PCs on with the MHs at all, or can they be shut down once the MHs come on so they just provide a sunrise/sunset period? I am using one actinic and one 6500k bulb in them, the MHs are 10000k bulbs.

All I have so far for corals are:

montipora digitata
green furry mushroom
green star polyp
kenya tree
zoanthids


I'm open to suggestions and reccomendations. Of course when my wife sees this months bill , she'll kill me and the whole thing will become irrelavant.