Greg, I'm sure you'll be OK with your choice, and I don't want to get in the middle of this capacity discussion, but all I can find on the web states 'up to' 500G
With that said ...
With a skimmer of this quality, I'm sure it will be fine for a heavy load. Not like a cheap skimmer where you cut the rating in half
I find info that states up to a whopping 2400lph of air flow, so I'd say you're good to go dude
