fixture

I'm doing some research into 1k watt DE complete fixtures. I know Gavita is one of the best + it works for the El1 + El2 Master controller. What makes a specific Ballast work with a master controller? I found a Complete fixture from Grow Co. and it says controller compatible: EL1, El2, or...

I was wondering if there is a general rule of thumb when it come to bulb/ ballasts compatibility? I know you cant use a CMH bulb in any of my old CH or HPS fixtures. But what about Compatibility between Bulb/ ballasts brand?

Hi, just a small problem with my COB fixture, its hanging down on 1 side so I cant hang it right now Currently I just have an eye hook in the centre on each end - then attaching my hanging ropes to that Should I try something like hanging from 4 corners instead? What are you COB DIYers doing...