I don't want to use tin foil this time around, and I've seen that foil that is all one big sheet and I'm wondering what store sells that or where I can buy some?
Quoted for truth. Panda film or mylar is the way to go. If you want cheap mylar, go to walmart or somewhere and buy a fire blanket.
Unless u have foil absolutely flat, you lose a ton of reflectivity. It also causes hot spots. Mylar is good too, but same problems. Flat matte white paint has been proven to be best, and cheaper. Hope this helps.
panda plastic or mylar. foil causes hot spots and can burn plants. it also krinkles easy and loses reflevtivity, just like freakbro said. white paint is good too. check out my grow http://forum.grasscity.com/general-indoor-growing/531815-1000w-mh-hps-lst-scrog-dwc-first-grow.html