Correct light distance

I almost want to argue the point of distance and want to say it's very important with LED's. I started my grow with cfl's. The last three weeks i bought a 240w blackstar led light and hooked it up. the results ? i had it to close (probably about 8 to 10 inches away from the plant) and all of my plants started showing what was referred to as sun bleaching or whatever you want to call it. pretty much most of my top leaves started to turn yellow and look pretty bad. i just harvested one plant and i have to order a larger tent to compensate for the led i put in there a few weeks ago. i would think there has o be some sort of standard when it comes to distance with led lights

It will depend on the make and model of LED.. Area-51 says 18" away for their SGS-160:

SGS-160 LED Grow Light
Unit Size: 12" wide, 18" long, 2.75" thick
Power Source: 48x Cree XPG Outdoor White + 24x Cree XPE Red
Electrical Consumption: 120w Veg Mode; 155w Flowering Mode (actual draw -/+ 5w)
Coverage: Minimum 24" x 24" ; Maximum 36" x 36" ; Recommended 24" x 36"
Recommended Height Above Canopy: 18"

source: http://area51lighting.com/the160.html

Check the manufacturers site for details on your specific light.. If they do not have one, you probably got a cheap chinese light and you should use that to decorate for the holidays.