vho vs pc (why is my pc brighter?)

[sponge man]

i currently have a 40 breeder reef. for the longest time i've had a hamilton vho set-up (2-96 watt bulbs). being that they are both next to each other, the back half of my tank is dim. i bought a current 1-96 watt pc just to light up the back a little. they problem being that the pc looks to be a least 10 times brighter. what's with that? is it possible that my vho's are working correctly? the bulbs are only 6 months old. should i buy a new vho set-up? any help would be great.:rolleyes:

[Navyblue]

May be different tube colour?

If my memory serves, I think PC's lumen rating is a tad higher than VHO watt for watt. I don't have hard number with me but you can try searching for that.