dimming your ballast will drastically change the life of your lamp as well as degrade the spectrum..I highly recommend switching to a "switchable" ballast that gives you the option to switch between 1000/600/400w. Some of these ballasts will allow you to run a 1000w lamp at a 600w setting, which...
Check out www.solis-tek.com...these guys have been around since 2009 and have a sick LED coming out. they were the first company to come out with a LCD/Remote controlled ballast with a remote..my buddy has 6 running with the matching bulbs and hoods..bright..highly recommend..:vap-leafy_wave: