I was going to point out that the mirrors aren't doing what you think they are doing. If anything about the only good it's doing is raising temps. If your room is cool or you are running a space heater, then leave the mirrors, otherwise I would suggest you use nothing as there is plenty of research that shows that mirrors don't reflect the kind of light your wanting. White paint, white plastic film, heck even tin foil is probably better then a mirror. Something to do with the silver paint that is used to make a mirror only absorbs light or some shit.

You can purchase panda film really cheap and in a quantity needed to surround your grow which is white on one side and black on the other. It;s a pretty useful product for many reasons I find.