Nevermind. I noticed how well some of the free fish for desktopx worked, and bought it. I bought every pack, it is awesome.
I have about 14 fish on the desktop right now, and staying under 10% (mostly under 5%) on the dual video cards.
It's awesome, my kids are going to love it too.
I'm off to try to find out how to get the expansion fish to show up, though